include/linux/lz4.h: add some missing macros

Currently, LZ4_DISTANCE_MAX and LZ4_DECOMPRESS_INPLACE_MARGIN are
defined in the erofs subsystem for LZ4 in-place decompression, which is
somewhat unsuit

include/linux/lz4.h: add some missing macros

Currently, LZ4_DISTANCE_MAX and LZ4_DECOMPRESS_INPLACE_MARGIN are
defined in the erofs subsystem for LZ4 in-place decompression, which is
somewhat unsuitable since they should belong to the LZ4 itself and
may change with future LZ4 codebase updates.

Move them to include/linux/lz4.h to match the upstream LZ4 library [1].
No logic changes.

[1] https://github.com/lz4/lz4/blob/v1.10.0/lib/lz4.h#L670

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Gao Xiang <[email protected]>
Cc: Yann Collet <[email protected]>
Cc: Nick Terrell <[email protected]>
Cc: Chao Yu <[email protected]>
Cc: Yue Hu <[email protected]>
Cc; Jeffle Xu <[email protected]>
Cc: Sandeep Dhavale <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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include/linux/lz4.h: fix spelling and copy-paste errors in documentation

Fix a few spelling and grammar errors, and two places where fast/safe in
the documentation did not match the function.

Link:

include/linux/lz4.h: fix spelling and copy-paste errors in documentation

Fix a few spelling and grammar errors, and two places where fast/safe in
the documentation did not match the function.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Tom Levy <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Jiri Kosina <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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lib/lz4: remove back-compat wrappers

Remove the functions introduced as wrappers for providing backwards
compatibility to the prior LZ4 version. They're not needed anymore
since there's no callers

lib/lz4: remove back-compat wrappers

Remove the functions introduced as wrappers for providing backwards
compatibility to the prior LZ4 version. They're not needed anymore
since there's no callers left.

Link: http://lkml.kernel.org/r/1486321748-19085-6-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt <[email protected]>
Cc: Bongkyu Kim <[email protected]>
Cc: Rui Salvaterra <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Anton Vorontsov <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Tony Luck <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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lib: update LZ4 compressor module

Patch series "Update LZ4 compressor module", v7.

This patchset updates the LZ4 compression module to a version based on
LZ4 v1.7.3 allowing to use the fast compres

lib: update LZ4 compressor module

Patch series "Update LZ4 compressor module", v7.

This patchset updates the LZ4 compression module to a version based on
LZ4 v1.7.3 allowing to use the fast compression algorithm aka LZ4 fast
which provides an "acceleration" parameter as a tradeoff between high
compression ratio and high compression speed.

We want to use LZ4 fast in order to support compression in lustre and
(mostly, based on that) investigate data reduction techniques in behalf
of storage systems.

Also, it will be useful for other users of LZ4 compression, as with LZ4
fast it is possible to enable applications to use fast and/or high
compression depending on the usecase. For instance, ZRAM is offering a
LZ4 backend and could benefit from an updated LZ4 in the kernel.

LZ4 homepage: http://www.lz4.org/
LZ4 source repository: https://github.com/lz4/lz4 Source version: 1.7.3

Benchmark (taken from [1], Core i5-4300U @1.9GHz):
----------------|--------------|----------------|----------
Compressor | Compression | Decompression | Ratio
----------------|--------------|----------------|----------
memcpy | 4200 MB/s | 4200 MB/s | 1.000
LZ4 fast 50 | 1080 MB/s | 2650 MB/s | 1.375
LZ4 fast 17 | 680 MB/s | 2220 MB/s | 1.607
LZ4 fast 5 | 475 MB/s | 1920 MB/s | 1.886
LZ4 default | 385 MB/s | 1850 MB/s | 2.101

[1] http://fastcompression.blogspot.de/2015/04/sampling-or-faster-lz4.html

[PATCH 1/5] lib: Update LZ4 compressor module
[PATCH 2/5] lib/decompress_unlz4: Change module to work with new LZ4 module version
[PATCH 3/5] crypto: Change LZ4 modules to work with new LZ4 module version
[PATCH 4/5] fs/pstore: fs/squashfs: Change usage of LZ4 to work with new LZ4 version
[PATCH 5/5] lib/lz4: Remove back-compat wrappers

This patch (of 5):

Update the LZ4 kernel module to LZ4 v1.7.3 by Yann Collet. The kernel
module is inspired by the previous work by Chanho Min. The updated LZ4
module will not break existing code since the patchset contains
appropriate changes.

API changes:

New method LZ4_compress_fast which differs from the variant available in
kernel by the new acceleration parameter, allowing to trade compression
ratio for more compression speed and vice versa.

LZ4_decompress_fast is the respective decompression method, featuring a
very fast decoder (multiple GB/s per core), able to reach RAM speed in
multi-core systems. The decompressor allows to decompress data
compressed with LZ4 fast as well as the LZ4 HC (high compression)
algorithm.

Also the useful functions LZ4_decompress_safe_partial and
LZ4_compress_destsize were added. The latter reverses the logic by
trying to compress as much data as possible from source to dest while
the former aims to decompress partial blocks of data.

A bunch of streaming functions were also added which allow
compressig/decompressing data in multiple steps (so called "streaming
mode").

The methods lz4_compress and lz4_decompress_unknownoutputsize are now
known as LZ4_compress_default respectivley LZ4_decompress_safe. The old
methods will be removed since there's no callers left in the code.

[[email protected]: fix KERNEL_LZ4 support]
Link: http://lkml.kernel.org/r/[email protected]
[[email protected]: simplify]
[[email protected]: fix the simplification]
[[email protected]: fix performance regressions]
Link: http://lkml.kernel.org/r/1486898178-17125-2-git-send-email-4sschmid@informatik.uni-hamburg.de
[[email protected]: v8]
Link: http://lkml.kernel.org/r/1487182598-15351-2-git-send-email-4sschmid@informatik.uni-hamburg.de
Link: http://lkml.kernel.org/r/1486321748-19085-2-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Cc: Bongkyu Kim <[email protected]>
Cc: Rui Salvaterra <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Anton Vorontsov <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Tony Luck <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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lz4: fix wrong compress buffer size for 64-bits

The current lz4 compress buffer is 16kb on 32-bits, 32kb on 64-bits
system. But, lz4 needs only 16kb on both. On 64-bits, this causes
wasted cpu cyc

lz4: fix wrong compress buffer size for 64-bits

The current lz4 compress buffer is 16kb on 32-bits, 32kb on 64-bits
system. But, lz4 needs only 16kb on both. On 64-bits, this causes
wasted cpu cycles for additional memset during every compression.

In case of lz4hc, the current buffer size is (256kb + 8) on 32-bits,
(512kb + 16) on 64-bits. But, lz4hc needs only (256kb + 2 * pointer) on
both.

This patch fixes these wrong compress buffer sizes for 64-bits.

Signed-off-by: Bongkyu Kim <[email protected]>
Cc: Chanho Min <[email protected]>
Cc: Yann Collet <[email protected]>
Cc: Kyungsik Lee <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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lz4: fix compression/decompression signedness mismatch

LZ4 compression and decompression functions require different in
signedness input/output parameters: unsigned char for compression and
signed c

lz4: fix compression/decompression signedness mismatch

LZ4 compression and decompression functions require different in
signedness input/output parameters: unsigned char for compression and
signed char for decompression.

Change decompression API to require "(const) unsigned char *".

Signed-off-by: Sergey Senozhatsky <[email protected]>
Cc: Kyungsik Lee <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Yann Collet <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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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 u

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.

[[email protected]: make lz4_compresshcctx() static]
Signed-off-by: Chanho Min <[email protected]>
Cc: "Darrick J. Wong" <[email protected]>
Cc: Bob Pearson <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Yann Collet <[email protected]>
Cc: Kyungsik Lee <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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decompressor: add LZ4 decompressor module

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

Benchmark Results

decompressor: add LZ4 decompressor module

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 <[email protected]>
Signed-off-by: Yann Collet <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Russell King <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Florian Fainelli <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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