From: Danny Wood Date: Fri, 27 Aug 2021 15:42:04 +0000 (+0100) Subject: universal7580: Backport LZ4 compression from Linux 4.1.52 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=64d8f575df4ab45584a767c0ee623f43d5ba68b4;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git universal7580: Backport LZ4 compression from Linux 4.1.52 * Enable it in our configs Change-Id: Ideb285d3678e479ede33b56e30e99062ec4884d6 --- diff --git a/arch/arm64/configs/lineageos_a3xelte_defconfig b/arch/arm64/configs/lineageos_a3xelte_defconfig index 8a35cd4d835..55aa29ec78e 100644 --- a/arch/arm64/configs/lineageos_a3xelte_defconfig +++ b/arch/arm64/configs/lineageos_a3xelte_defconfig @@ -1031,7 +1031,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -4023,6 +4023,8 @@ CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y CONFIG_LZO_DECOMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set diff --git a/arch/arm64/configs/lineageos_a5xelte_defconfig b/arch/arm64/configs/lineageos_a5xelte_defconfig index 797ede8123d..4a43da5e9ef 100644 --- a/arch/arm64/configs/lineageos_a5xelte_defconfig +++ b/arch/arm64/configs/lineageos_a5xelte_defconfig @@ -1031,7 +1031,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -4034,6 +4034,8 @@ CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y CONFIG_LZO_DECOMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set diff --git a/arch/arm64/configs/lineageos_a7xelte_defconfig b/arch/arm64/configs/lineageos_a7xelte_defconfig index 35e0d464681..9f77a3a3027 100644 --- a/arch/arm64/configs/lineageos_a7xelte_defconfig +++ b/arch/arm64/configs/lineageos_a7xelte_defconfig @@ -1031,7 +1031,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -4034,6 +4034,8 @@ CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y CONFIG_LZO_DECOMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set diff --git a/arch/arm64/configs/lineageos_j7elte_defconfig b/arch/arm64/configs/lineageos_j7elte_defconfig index 4ea4d3475f5..ca0c10a34ca 100644 --- a/arch/arm64/configs/lineageos_j7elte_defconfig +++ b/arch/arm64/configs/lineageos_j7elte_defconfig @@ -1014,7 +1014,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -3999,6 +3999,8 @@ CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y CONFIG_LZO_DECOMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set diff --git a/arch/arm64/configs/lineageos_j7xlte_defconfig b/arch/arm64/configs/lineageos_j7xlte_defconfig index b1bfb86f832..332a84f650b 100644 --- a/arch/arm64/configs/lineageos_j7xlte_defconfig +++ b/arch/arm64/configs/lineageos_j7xlte_defconfig @@ -1033,7 +1033,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -4023,6 +4023,8 @@ CONFIG_AUDIT_GENERIC=y CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_LZO_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set diff --git a/arch/arm64/configs/lineageos_s5neolte_defconfig b/arch/arm64/configs/lineageos_s5neolte_defconfig index 0d0098f9bfd..104aadd24c3 100644 --- a/arch/arm64/configs/lineageos_s5neolte_defconfig +++ b/arch/arm64/configs/lineageos_s5neolte_defconfig @@ -1029,7 +1029,7 @@ CONFIG_OF_RESERVED_MEM=y # CONFIG_PARPORT is not set CONFIG_BLK_DEV=y CONFIG_ZRAM=y -# CONFIG_ZRAM_LZ4_COMPRESS is not set +CONFIG_ZRAM_LZ4_COMPRESS=y # CONFIG_ZRAM_DEBUG is not set # CONFIG_BLK_DEV_COW_COMMON is not set CONFIG_BLK_DEV_LOOP=y @@ -4052,6 +4052,8 @@ CONFIG_ZLIB_INFLATE=y CONFIG_ZLIB_DEFLATE=y CONFIG_LZO_COMPRESS=y CONFIG_LZO_DECOMPRESS=y +CONFIG_LZ4_COMPRESS=y +CONFIG_LZ4_DECOMPRESS=y CONFIG_XZ_DEC=y # CONFIG_XZ_DEC_X86 is not set # CONFIG_XZ_DEC_POWERPC is not set diff --git a/include/linux/lz4.h b/include/linux/lz4.h new file mode 100644 index 00000000000..4356686b0a3 --- /dev/null +++ b/include/linux/lz4.h @@ -0,0 +1,87 @@ +#ifndef __LZ4_H__ +#define __LZ4_H__ +/* + * LZ4 Kernel Interface + * + * Copyright (C) 2013, LG Electronics, Kyungsik Lee + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#define LZ4_MEM_COMPRESS (4096 * sizeof(unsigned char *)) +#define LZ4HC_MEM_COMPRESS (65538 * sizeof(unsigned char *)) + +/* + * lz4_compressbound() + * Provides the maximum size that LZ4 may output in a "worst case" scenario + * (input data not compressible) + */ +static inline size_t lz4_compressbound(size_t isize) +{ + return isize + (isize / 255) + 16; +} + +/* + * lz4_compress() + * src : source address of the original data + * src_len : size of the original data + * dst : output buffer address of the compressed data + * This requires 'dst' of size LZ4_COMPRESSBOUND. + * dst_len : is the output size, which is returned after compress done + * workmem : address of the working memory. + * This requires 'workmem' of size LZ4_MEM_COMPRESS. + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer and workmem must be already allocated with + * the defined size. + */ +int lz4_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem); + + /* + * lz4hc_compress() + * src : source address of the original data + * src_len : size of the original data + * dst : output buffer address of the compressed data + * This requires 'dst' of size LZ4_COMPRESSBOUND. + * dst_len : is the output size, which is returned after compress done + * workmem : address of the working memory. + * This requires 'workmem' of size LZ4HC_MEM_COMPRESS. + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer and workmem must be already allocated with + * the defined size. + */ +int lz4hc_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem); + +/* + * lz4_decompress() + * src : source address of the compressed data + * src_len : is the input size, whcih is returned after decompress done + * dest : output buffer address of the decompressed data + * actual_dest_len: is the size of uncompressed data, supposing it's known + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer must be already allocated. + * slightly faster than lz4_decompress_unknownoutputsize() + */ +int lz4_decompress(const unsigned char *src, size_t *src_len, + unsigned char *dest, size_t actual_dest_len); + +/* + * lz4_decompress_unknownoutputsize() + * src : source address of the compressed data + * src_len : is the input size, therefore the compressed size + * dest : output buffer address of the decompressed data + * dest_len: is the max size of the destination buffer, which is + * returned with actual size of decompressed data after + * decompress done + * return : Success if return 0 + * Error if return (< 0) + * note : Destination buffer must be already allocated. + */ +int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len, + unsigned char *dest, size_t *dest_len); +#endif diff --git a/lib/Kconfig b/lib/Kconfig index fe01d418b09..d526e109b14 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -189,6 +189,15 @@ config LZO_COMPRESS config LZO_DECOMPRESS tristate +config LZ4_COMPRESS + tristate + +config LZ4HC_COMPRESS + tristate + +config LZ4_DECOMPRESS + tristate + source "lib/xz/Kconfig" # @@ -213,6 +222,10 @@ config DECOMPRESS_LZO select LZO_DECOMPRESS tristate +config DECOMPRESS_LZ4 + select LZ4_DECOMPRESS + tristate + # # Generic allocator support is selected if needed # diff --git a/lib/Makefile b/lib/Makefile index 9efe480b975..b6d7848a526 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -76,6 +76,9 @@ obj-$(CONFIG_REED_SOLOMON) += reed_solomon/ obj-$(CONFIG_BCH) += bch.o obj-$(CONFIG_LZO_COMPRESS) += lzo/ obj-$(CONFIG_LZO_DECOMPRESS) += lzo/ +obj-$(CONFIG_LZ4_COMPRESS) += lz4/ +obj-$(CONFIG_LZ4HC_COMPRESS) += lz4/ +obj-$(CONFIG_LZ4_DECOMPRESS) += lz4/ obj-$(CONFIG_XZ_DEC) += xz/ obj-$(CONFIG_RAID6_PQ) += raid6/ diff --git a/lib/lz4/Makefile b/lib/lz4/Makefile new file mode 100644 index 00000000000..8085d04e930 --- /dev/null +++ b/lib/lz4/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o +obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o +obj-$(CONFIG_LZ4_DECOMPRESS) += lz4_decompress.o diff --git a/lib/lz4/lz4_compress.c b/lib/lz4/lz4_compress.c new file mode 100644 index 00000000000..28321d8f75e --- /dev/null +++ b/lib/lz4/lz4_compress.c @@ -0,0 +1,443 @@ +/* + * LZ4 - Fast LZ compression algorithm + * Copyright (C) 2011-2012, Yann Collet. + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You can contact the author at : + * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html + * - LZ4 source repository : http://code.google.com/p/lz4/ + * + * Changed for kernel use by: + * Chanho Min + */ + +#include +#include +#include +#include +#include "lz4defs.h" + +/* + * LZ4_compressCtx : + * ----------------- + * Compress 'isize' bytes from 'source' into an output buffer 'dest' of + * maximum size 'maxOutputSize'. * If it cannot achieve it, compression + * will stop, and result of the function will be zero. + * return : the number of bytes written in buffer 'dest', or 0 if the + * compression fails + */ +static inline int lz4_compressctx(void *ctx, + const char *source, + char *dest, + int isize, + int maxoutputsize) +{ + HTYPE *hashtable = (HTYPE *)ctx; + const u8 *ip = (u8 *)source; +#if LZ4_ARCH64 + const BYTE * const base = ip; +#else + const int base = 0; +#endif + const u8 *anchor = ip; + const u8 *const iend = ip + isize; + const u8 *const mflimit = iend - MFLIMIT; + #define MATCHLIMIT (iend - LASTLITERALS) + + u8 *op = (u8 *) dest; + u8 *const oend = op + maxoutputsize; + int length; + const int skipstrength = SKIPSTRENGTH; + u32 forwardh; + int lastrun; + + /* Init */ + if (isize < MINLENGTH) + goto _last_literals; + + memset((void *)hashtable, 0, LZ4_MEM_COMPRESS); + + /* First Byte */ + hashtable[LZ4_HASH_VALUE(ip)] = ip - base; + ip++; + forwardh = LZ4_HASH_VALUE(ip); + + /* Main Loop */ + for (;;) { + int findmatchattempts = (1U << skipstrength) + 3; + const u8 *forwardip = ip; + const u8 *ref; + u8 *token; + + /* Find a match */ + do { + u32 h = forwardh; + int step = findmatchattempts++ >> skipstrength; + ip = forwardip; + forwardip = ip + step; + + if (unlikely(forwardip > mflimit)) + goto _last_literals; + + forwardh = LZ4_HASH_VALUE(forwardip); + ref = base + hashtable[h]; + hashtable[h] = ip - base; + } while ((ref < ip - MAX_DISTANCE) || (A32(ref) != A32(ip))); + + /* Catch up */ + while ((ip > anchor) && (ref > (u8 *)source) && + unlikely(ip[-1] == ref[-1])) { + ip--; + ref--; + } + + /* Encode Literal length */ + length = (int)(ip - anchor); + token = op++; + /* check output limit */ + if (unlikely(op + length + (2 + 1 + LASTLITERALS) + + (length >> 8) > oend)) + return 0; + + if (length >= (int)RUN_MASK) { + int len; + *token = (RUN_MASK << ML_BITS); + len = length - RUN_MASK; + for (; len > 254 ; len -= 255) + *op++ = 255; + *op++ = (u8)len; + } else + *token = (length << ML_BITS); + + /* Copy Literals */ + LZ4_BLINDCOPY(anchor, op, length); +_next_match: + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref)); + + /* Start Counting */ + ip += MINMATCH; + /* MinMatch verified */ + ref += MINMATCH; + anchor = ip; + while (likely(ip < MATCHLIMIT - (STEPSIZE - 1))) { + #if LZ4_ARCH64 + u64 diff = A64(ref) ^ A64(ip); + #else + u32 diff = A32(ref) ^ A32(ip); + #endif + if (!diff) { + ip += STEPSIZE; + ref += STEPSIZE; + continue; + } + ip += LZ4_NBCOMMONBYTES(diff); + goto _endcount; + } + #if LZ4_ARCH64 + if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) { + ip += 4; + ref += 4; + } + #endif + if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) { + ip += 2; + ref += 2; + } + if ((ip < MATCHLIMIT) && (*ref == *ip)) + ip++; +_endcount: + /* Encode MatchLength */ + length = (int)(ip - anchor); + /* Check output limit */ + if (unlikely(op + (1 + LASTLITERALS) + (length >> 8) > oend)) + return 0; + if (length >= (int)ML_MASK) { + *token += ML_MASK; + length -= ML_MASK; + for (; length > 509 ; length -= 510) { + *op++ = 255; + *op++ = 255; + } + if (length > 254) { + length -= 255; + *op++ = 255; + } + *op++ = (u8)length; + } else + *token += length; + + /* Test end of chunk */ + if (ip > mflimit) { + anchor = ip; + break; + } + + /* Fill table */ + hashtable[LZ4_HASH_VALUE(ip-2)] = ip - 2 - base; + + /* Test next position */ + ref = base + hashtable[LZ4_HASH_VALUE(ip)]; + hashtable[LZ4_HASH_VALUE(ip)] = ip - base; + if ((ref > ip - (MAX_DISTANCE + 1)) && (A32(ref) == A32(ip))) { + token = op++; + *token = 0; + goto _next_match; + } + + /* Prepare next loop */ + anchor = ip++; + forwardh = LZ4_HASH_VALUE(ip); + } + +_last_literals: + /* Encode Last Literals */ + lastrun = (int)(iend - anchor); + if (((char *)op - dest) + lastrun + 1 + + ((lastrun + 255 - RUN_MASK) / 255) > (u32)maxoutputsize) + return 0; + + if (lastrun >= (int)RUN_MASK) { + *op++ = (RUN_MASK << ML_BITS); + lastrun -= RUN_MASK; + for (; lastrun > 254 ; lastrun -= 255) + *op++ = 255; + *op++ = (u8)lastrun; + } else + *op++ = (lastrun << ML_BITS); + memcpy(op, anchor, iend - anchor); + op += iend - anchor; + + /* End */ + return (int)(((char *)op) - dest); +} + +static inline int lz4_compress64kctx(void *ctx, + const char *source, + char *dest, + int isize, + int maxoutputsize) +{ + u16 *hashtable = (u16 *)ctx; + const u8 *ip = (u8 *) source; + const u8 *anchor = ip; + const u8 *const base = ip; + const u8 *const iend = ip + isize; + const u8 *const mflimit = iend - MFLIMIT; + #define MATCHLIMIT (iend - LASTLITERALS) + + u8 *op = (u8 *) dest; + u8 *const oend = op + maxoutputsize; + int len, length; + const int skipstrength = SKIPSTRENGTH; + u32 forwardh; + int lastrun; + + /* Init */ + if (isize < MINLENGTH) + goto _last_literals; + + memset((void *)hashtable, 0, LZ4_MEM_COMPRESS); + + /* First Byte */ + ip++; + forwardh = LZ4_HASH64K_VALUE(ip); + + /* Main Loop */ + for (;;) { + int findmatchattempts = (1U << skipstrength) + 3; + const u8 *forwardip = ip; + const u8 *ref; + u8 *token; + + /* Find a match */ + do { + u32 h = forwardh; + int step = findmatchattempts++ >> skipstrength; + ip = forwardip; + forwardip = ip + step; + + if (forwardip > mflimit) + goto _last_literals; + + forwardh = LZ4_HASH64K_VALUE(forwardip); + ref = base + hashtable[h]; + hashtable[h] = (u16)(ip - base); + } while (A32(ref) != A32(ip)); + + /* Catch up */ + while ((ip > anchor) && (ref > (u8 *)source) + && (ip[-1] == ref[-1])) { + ip--; + ref--; + } + + /* Encode Literal length */ + length = (int)(ip - anchor); + token = op++; + /* Check output limit */ + if (unlikely(op + length + (2 + 1 + LASTLITERALS) + + (length >> 8) > oend)) + return 0; + if (length >= (int)RUN_MASK) { + *token = (RUN_MASK << ML_BITS); + len = length - RUN_MASK; + for (; len > 254 ; len -= 255) + *op++ = 255; + *op++ = (u8)len; + } else + *token = (length << ML_BITS); + + /* Copy Literals */ + LZ4_BLINDCOPY(anchor, op, length); + +_next_match: + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(op, (u16)(ip - ref)); + + /* Start Counting */ + ip += MINMATCH; + /* MinMatch verified */ + ref += MINMATCH; + anchor = ip; + + while (ip < MATCHLIMIT - (STEPSIZE - 1)) { + #if LZ4_ARCH64 + u64 diff = A64(ref) ^ A64(ip); + #else + u32 diff = A32(ref) ^ A32(ip); + #endif + + if (!diff) { + ip += STEPSIZE; + ref += STEPSIZE; + continue; + } + ip += LZ4_NBCOMMONBYTES(diff); + goto _endcount; + } + #if LZ4_ARCH64 + if ((ip < (MATCHLIMIT - 3)) && (A32(ref) == A32(ip))) { + ip += 4; + ref += 4; + } + #endif + if ((ip < (MATCHLIMIT - 1)) && (A16(ref) == A16(ip))) { + ip += 2; + ref += 2; + } + if ((ip < MATCHLIMIT) && (*ref == *ip)) + ip++; +_endcount: + + /* Encode MatchLength */ + len = (int)(ip - anchor); + /* Check output limit */ + if (unlikely(op + (1 + LASTLITERALS) + (len >> 8) > oend)) + return 0; + if (len >= (int)ML_MASK) { + *token += ML_MASK; + len -= ML_MASK; + for (; len > 509 ; len -= 510) { + *op++ = 255; + *op++ = 255; + } + if (len > 254) { + len -= 255; + *op++ = 255; + } + *op++ = (u8)len; + } else + *token += len; + + /* Test end of chunk */ + if (ip > mflimit) { + anchor = ip; + break; + } + + /* Fill table */ + hashtable[LZ4_HASH64K_VALUE(ip-2)] = (u16)(ip - 2 - base); + + /* Test next position */ + ref = base + hashtable[LZ4_HASH64K_VALUE(ip)]; + hashtable[LZ4_HASH64K_VALUE(ip)] = (u16)(ip - base); + if (A32(ref) == A32(ip)) { + token = op++; + *token = 0; + goto _next_match; + } + + /* Prepare next loop */ + anchor = ip++; + forwardh = LZ4_HASH64K_VALUE(ip); + } + +_last_literals: + /* Encode Last Literals */ + lastrun = (int)(iend - anchor); + if (op + lastrun + 1 + (lastrun - RUN_MASK + 255) / 255 > oend) + return 0; + if (lastrun >= (int)RUN_MASK) { + *op++ = (RUN_MASK << ML_BITS); + lastrun -= RUN_MASK; + for (; lastrun > 254 ; lastrun -= 255) + *op++ = 255; + *op++ = (u8)lastrun; + } else + *op++ = (lastrun << ML_BITS); + memcpy(op, anchor, iend - anchor); + op += iend - anchor; + /* End */ + return (int)(((char *)op) - dest); +} + +int lz4_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem) +{ + int ret = -1; + int out_len = 0; + + if (src_len < LZ4_64KLIMIT) + out_len = lz4_compress64kctx(wrkmem, src, dst, src_len, + lz4_compressbound(src_len)); + else + out_len = lz4_compressctx(wrkmem, src, dst, src_len, + lz4_compressbound(src_len)); + + if (out_len < 0) + goto exit; + + *dst_len = out_len; + + return 0; +exit: + return ret; +} +EXPORT_SYMBOL(lz4_compress); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("LZ4 compressor"); diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c new file mode 100644 index 00000000000..26cc6029b28 --- /dev/null +++ b/lib/lz4/lz4_decompress.c @@ -0,0 +1,333 @@ +/* + * LZ4 Decompressor for Linux kernel + * + * Copyright (C) 2013, LG Electronics, Kyungsik Lee + * + * Based on LZ4 implementation by Yann Collet. + * + * LZ4 - Fast LZ compression algorithm + * Copyright (C) 2011-2012, Yann Collet. + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You can contact the author at : + * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html + * - LZ4 source repository : http://code.google.com/p/lz4/ + */ + +#ifndef STATIC +#include +#include +#endif +#include + +#include + +#include "lz4defs.h" + +static const int dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; +#if LZ4_ARCH64 +static const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3}; +#endif + +static int lz4_uncompress(const char *source, char *dest, int osize) +{ + const BYTE *ip = (const BYTE *) source; + const BYTE *ref; + BYTE *op = (BYTE *) dest; + BYTE * const oend = op + osize; + BYTE *cpy; + unsigned token; + size_t length; + + while (1) { + + /* get runlength */ + token = *ip++; + length = (token >> ML_BITS); + if (length == RUN_MASK) { + size_t len; + + len = *ip++; + for (; len == 255; length += 255) + len = *ip++; + if (unlikely(length > (size_t)(length + len))) + goto _output_error; + length += len; + } + + /* copy literals */ + cpy = op + length; + if (unlikely(cpy > oend - COPYLENGTH)) { + /* + * Error: not enough place for another match + * (min 4) + 5 literals + */ + if (cpy != oend) + goto _output_error; + + memcpy(op, ip, length); + ip += length; + break; /* EOF */ + } + LZ4_WILDCOPY(ip, op, cpy); + ip -= (op - cpy); + op = cpy; + + /* get offset */ + LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip); + ip += 2; + + /* Error: offset create reference outside destination buffer */ + if (unlikely(ref < (BYTE *const) dest)) + goto _output_error; + + /* get matchlength */ + length = token & ML_MASK; + if (length == ML_MASK) { + for (; *ip == 255; length += 255) + ip++; + if (unlikely(length > (size_t)(length + *ip))) + goto _output_error; + length += *ip++; + } + + /* copy repeated sequence */ + if (unlikely((op - ref) < STEPSIZE)) { +#if LZ4_ARCH64 + int dec64 = dec64table[op - ref]; +#else + const int dec64 = 0; +#endif + op[0] = ref[0]; + op[1] = ref[1]; + op[2] = ref[2]; + op[3] = ref[3]; + op += 4; + ref += 4; + ref -= dec32table[op-ref]; + PUT4(ref, op); + op += STEPSIZE - 4; + ref -= dec64; + } else { + LZ4_COPYSTEP(ref, op); + } + cpy = op + length - (STEPSIZE - 4); + if (cpy > (oend - COPYLENGTH)) { + + /* Error: request to write beyond destination buffer */ + if (cpy > oend) + goto _output_error; + if ((ref + COPYLENGTH) > oend || + (op + COPYLENGTH) > oend) + goto _output_error; + LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH)); + while (op < cpy) + *op++ = *ref++; + op = cpy; + /* + * Check EOF (should never happen, since last 5 bytes + * are supposed to be literals) + */ + if (op == oend) + goto _output_error; + continue; + } + LZ4_SECURECOPY(ref, op, cpy); + op = cpy; /* correction */ + } + /* end of decoding */ + return (int) (((char *)ip) - source); + + /* write overflow error detected */ +_output_error: + return -1; +} + +static int lz4_uncompress_unknownoutputsize(const char *source, char *dest, + int isize, size_t maxoutputsize) +{ + const BYTE *ip = (const BYTE *) source; + const BYTE *const iend = ip + isize; + const BYTE *ref; + + + BYTE *op = (BYTE *) dest; + BYTE * const oend = op + maxoutputsize; + BYTE *cpy; + + /* Main Loop */ + while (ip < iend) { + + unsigned token; + size_t length; + + /* get runlength */ + token = *ip++; + length = (token >> ML_BITS); + if (length == RUN_MASK) { + int s = 255; + while ((ip < iend) && (s == 255)) { + s = *ip++; + if (unlikely(length > (size_t)(length + s))) + goto _output_error; + length += s; + } + } + /* copy literals */ + cpy = op + length; + if ((cpy > oend - COPYLENGTH) || + (ip + length > iend - COPYLENGTH)) { + + if (cpy > oend) + goto _output_error;/* writes beyond buffer */ + + if (ip + length != iend) + goto _output_error;/* + * Error: LZ4 format requires + * to consume all input + * at this stage + */ + memcpy(op, ip, length); + op += length; + break;/* Necessarily EOF, due to parsing restrictions */ + } + LZ4_WILDCOPY(ip, op, cpy); + ip -= (op - cpy); + op = cpy; + + /* get offset */ + LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip); + ip += 2; + if (ref < (BYTE * const) dest) + goto _output_error; + /* + * Error : offset creates reference + * outside of destination buffer + */ + + /* get matchlength */ + length = (token & ML_MASK); + if (length == ML_MASK) { + while (ip < iend) { + int s = *ip++; + if (unlikely(length > (size_t)(length + s))) + goto _output_error; + length += s; + if (s == 255) + continue; + break; + } + } + + /* copy repeated sequence */ + if (unlikely((op - ref) < STEPSIZE)) { +#if LZ4_ARCH64 + int dec64 = dec64table[op - ref]; +#else + const int dec64 = 0; +#endif + op[0] = ref[0]; + op[1] = ref[1]; + op[2] = ref[2]; + op[3] = ref[3]; + op += 4; + ref += 4; + ref -= dec32table[op - ref]; + PUT4(ref, op); + op += STEPSIZE - 4; + ref -= dec64; + } else { + LZ4_COPYSTEP(ref, op); + } + cpy = op + length - (STEPSIZE-4); + if (cpy > oend - COPYLENGTH) { + if (cpy > oend) + goto _output_error; /* write outside of buf */ + + LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH)); + while (op < cpy) + *op++ = *ref++; + op = cpy; + /* + * Check EOF (should never happen, since last 5 bytes + * are supposed to be literals) + */ + if (op == oend) + goto _output_error; + continue; + } + LZ4_SECURECOPY(ref, op, cpy); + op = cpy; /* correction */ + } + /* end of decoding */ + return (int) (((char *) op) - dest); + + /* write overflow error detected */ +_output_error: + return -1; +} + +int lz4_decompress(const unsigned char *src, size_t *src_len, + unsigned char *dest, size_t actual_dest_len) +{ + int ret = -1; + int input_len = 0; + + input_len = lz4_uncompress(src, dest, actual_dest_len); + if (input_len < 0) + goto exit_0; + *src_len = input_len; + + return 0; +exit_0: + return ret; +} +#ifndef STATIC +EXPORT_SYMBOL(lz4_decompress); +#endif + +int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len, + unsigned char *dest, size_t *dest_len) +{ + int ret = -1; + int out_len = 0; + + out_len = lz4_uncompress_unknownoutputsize(src, dest, src_len, + *dest_len); + if (out_len < 0) + goto exit_0; + *dest_len = out_len; + + return 0; +exit_0: + return ret; +} +#ifndef STATIC +EXPORT_SYMBOL(lz4_decompress_unknownoutputsize); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("LZ4 Decompressor"); +#endif diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h new file mode 100644 index 00000000000..0710a62ad2f --- /dev/null +++ b/lib/lz4/lz4defs.h @@ -0,0 +1,159 @@ +/* + * lz4defs.h -- architecture specific defines + * + * Copyright (C) 2013, LG Electronics, Kyungsik Lee + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +/* + * Detects 64 bits mode + */ +#if defined(CONFIG_64BIT) +#define LZ4_ARCH64 1 +#else +#define LZ4_ARCH64 0 +#endif + +/* + * Architecture-specific macros + */ +#define BYTE u8 +typedef struct _U16_S { u16 v; } U16_S; +typedef struct _U32_S { u32 v; } U32_S; +typedef struct _U64_S { u64 v; } U64_S; +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) \ + || defined(CONFIG_ARM) && __LINUX_ARM_ARCH__ >= 6 \ + && defined(ARM_EFFICIENT_UNALIGNED_ACCESS) + +#define A16(x) (((U16_S *)(x))->v) +#define A32(x) (((U32_S *)(x))->v) +#define A64(x) (((U64_S *)(x))->v) + +#define PUT4(s, d) (A32(d) = A32(s)) +#define PUT8(s, d) (A64(d) = A64(s)) + +#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \ + (d = s - A16(p)) + +#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \ + do { \ + A16(p) = v; \ + p += 2; \ + } while (0) +#else /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */ + +#define A64(x) get_unaligned((u64 *)&(((U16_S *)(x))->v)) +#define A32(x) get_unaligned((u32 *)&(((U16_S *)(x))->v)) +#define A16(x) get_unaligned((u16 *)&(((U16_S *)(x))->v)) + +#define PUT4(s, d) \ + put_unaligned(get_unaligned((const u32 *) s), (u32 *) d) +#define PUT8(s, d) \ + put_unaligned(get_unaligned((const u64 *) s), (u64 *) d) + +#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \ + (d = s - get_unaligned_le16(p)) + +#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \ + do { \ + put_unaligned_le16(v, (u16 *)(p)); \ + p += 2; \ + } while (0) +#endif + +#define COPYLENGTH 8 +#define ML_BITS 4 +#define ML_MASK ((1U << ML_BITS) - 1) +#define RUN_BITS (8 - ML_BITS) +#define RUN_MASK ((1U << RUN_BITS) - 1) +#define MEMORY_USAGE 14 +#define MINMATCH 4 +#define SKIPSTRENGTH 6 +#define LASTLITERALS 5 +#define MFLIMIT (COPYLENGTH + MINMATCH) +#define MINLENGTH (MFLIMIT + 1) +#define MAXD_LOG 16 +#define MAXD (1 << MAXD_LOG) +#define MAXD_MASK (u32)(MAXD - 1) +#define MAX_DISTANCE (MAXD - 1) +#define HASH_LOG (MAXD_LOG - 1) +#define HASHTABLESIZE (1 << HASH_LOG) +#define MAX_NB_ATTEMPTS 256 +#define OPTIMAL_ML (int)((ML_MASK-1)+MINMATCH) +#define LZ4_64KLIMIT ((1<<16) + (MFLIMIT - 1)) +#define HASHLOG64K ((MEMORY_USAGE - 2) + 1) +#define HASH64KTABLESIZE (1U << HASHLOG64K) +#define LZ4_HASH_VALUE(p) (((A32(p)) * 2654435761U) >> \ + ((MINMATCH * 8) - (MEMORY_USAGE-2))) +#define LZ4_HASH64K_VALUE(p) (((A32(p)) * 2654435761U) >> \ + ((MINMATCH * 8) - HASHLOG64K)) +#define HASH_VALUE(p) (((A32(p)) * 2654435761U) >> \ + ((MINMATCH * 8) - HASH_LOG)) + +#if LZ4_ARCH64/* 64-bit */ +#define STEPSIZE 8 + +#define LZ4_COPYSTEP(s, d) \ + do { \ + PUT8(s, d); \ + d += 8; \ + s += 8; \ + } while (0) + +#define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d) + +#define LZ4_SECURECOPY(s, d, e) \ + do { \ + if (d < e) { \ + LZ4_WILDCOPY(s, d, e); \ + } \ + } while (0) +#define HTYPE u32 + +#ifdef __BIG_ENDIAN +#define LZ4_NBCOMMONBYTES(val) (__builtin_clzll(val) >> 3) +#else +#define LZ4_NBCOMMONBYTES(val) (__builtin_ctzll(val) >> 3) +#endif + +#else /* 32-bit */ +#define STEPSIZE 4 + +#define LZ4_COPYSTEP(s, d) \ + do { \ + PUT4(s, d); \ + d += 4; \ + s += 4; \ + } while (0) + +#define LZ4_COPYPACKET(s, d) \ + do { \ + LZ4_COPYSTEP(s, d); \ + LZ4_COPYSTEP(s, d); \ + } while (0) + +#define LZ4_SECURECOPY LZ4_WILDCOPY +#define HTYPE const u8* + +#ifdef __BIG_ENDIAN +#define LZ4_NBCOMMONBYTES(val) (__builtin_clz(val) >> 3) +#else +#define LZ4_NBCOMMONBYTES(val) (__builtin_ctz(val) >> 3) +#endif + +#endif + +#define LZ4_WILDCOPY(s, d, e) \ + do { \ + LZ4_COPYPACKET(s, d); \ + } while (d < e) + +#define LZ4_BLINDCOPY(s, d, l) \ + do { \ + u8 *e = (d) + l; \ + LZ4_WILDCOPY(s, d, e); \ + d = e; \ + } while (0) diff --git a/lib/lz4/lz4hc_compress.c b/lib/lz4/lz4hc_compress.c new file mode 100644 index 00000000000..f344f76b655 --- /dev/null +++ b/lib/lz4/lz4hc_compress.c @@ -0,0 +1,539 @@ +/* + * LZ4 HC - High Compression Mode of LZ4 + * Copyright (C) 2011-2012, Yann Collet. + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You can contact the author at : + * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html + * - LZ4 source repository : http://code.google.com/p/lz4/ + * + * Changed for kernel use by: + * Chanho Min + */ + +#include +#include +#include +#include +#include "lz4defs.h" + +struct lz4hc_data { + const u8 *base; + HTYPE hashtable[HASHTABLESIZE]; + u16 chaintable[MAXD]; + const u8 *nexttoupdate; +} __attribute__((__packed__)); + +static inline int lz4hc_init(struct lz4hc_data *hc4, const u8 *base) +{ + memset((void *)hc4->hashtable, 0, sizeof(hc4->hashtable)); + memset(hc4->chaintable, 0xFF, sizeof(hc4->chaintable)); + +#if LZ4_ARCH64 + hc4->nexttoupdate = base + 1; +#else + hc4->nexttoupdate = base; +#endif + hc4->base = base; + return 1; +} + +/* Update chains up to ip (excluded) */ +static inline void lz4hc_insert(struct lz4hc_data *hc4, const u8 *ip) +{ + u16 *chaintable = hc4->chaintable; + HTYPE *hashtable = hc4->hashtable; +#if LZ4_ARCH64 + const BYTE * const base = hc4->base; +#else + const int base = 0; +#endif + + while (hc4->nexttoupdate < ip) { + const u8 *p = hc4->nexttoupdate; + size_t delta = p - (hashtable[HASH_VALUE(p)] + base); + if (delta > MAX_DISTANCE) + delta = MAX_DISTANCE; + chaintable[(size_t)(p) & MAXD_MASK] = (u16)delta; + hashtable[HASH_VALUE(p)] = (p) - base; + hc4->nexttoupdate++; + } +} + +static inline size_t lz4hc_commonlength(const u8 *p1, const u8 *p2, + const u8 *const matchlimit) +{ + const u8 *p1t = p1; + + while (p1t < matchlimit - (STEPSIZE - 1)) { +#if LZ4_ARCH64 + u64 diff = A64(p2) ^ A64(p1t); +#else + u32 diff = A32(p2) ^ A32(p1t); +#endif + if (!diff) { + p1t += STEPSIZE; + p2 += STEPSIZE; + continue; + } + p1t += LZ4_NBCOMMONBYTES(diff); + return p1t - p1; + } +#if LZ4_ARCH64 + if ((p1t < (matchlimit-3)) && (A32(p2) == A32(p1t))) { + p1t += 4; + p2 += 4; + } +#endif + + if ((p1t < (matchlimit - 1)) && (A16(p2) == A16(p1t))) { + p1t += 2; + p2 += 2; + } + if ((p1t < matchlimit) && (*p2 == *p1t)) + p1t++; + return p1t - p1; +} + +static inline int lz4hc_insertandfindbestmatch(struct lz4hc_data *hc4, + const u8 *ip, const u8 *const matchlimit, const u8 **matchpos) +{ + u16 *const chaintable = hc4->chaintable; + HTYPE *const hashtable = hc4->hashtable; + const u8 *ref; +#if LZ4_ARCH64 + const BYTE * const base = hc4->base; +#else + const int base = 0; +#endif + int nbattempts = MAX_NB_ATTEMPTS; + size_t repl = 0, ml = 0; + u16 delta; + + /* HC4 match finder */ + lz4hc_insert(hc4, ip); + ref = hashtable[HASH_VALUE(ip)] + base; + + /* potential repetition */ + if (ref >= ip-4) { + /* confirmed */ + if (A32(ref) == A32(ip)) { + delta = (u16)(ip-ref); + repl = ml = lz4hc_commonlength(ip + MINMATCH, + ref + MINMATCH, matchlimit) + MINMATCH; + *matchpos = ref; + } + ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK]; + } + + while ((ref >= ip - MAX_DISTANCE) && nbattempts) { + nbattempts--; + if (*(ref + ml) == *(ip + ml)) { + if (A32(ref) == A32(ip)) { + size_t mlt = + lz4hc_commonlength(ip + MINMATCH, + ref + MINMATCH, matchlimit) + MINMATCH; + if (mlt > ml) { + ml = mlt; + *matchpos = ref; + } + } + } + ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK]; + } + + /* Complete table */ + if (repl) { + const BYTE *ptr = ip; + const BYTE *end; + end = ip + repl - (MINMATCH-1); + /* Pre-Load */ + while (ptr < end - delta) { + chaintable[(size_t)(ptr) & MAXD_MASK] = delta; + ptr++; + } + do { + chaintable[(size_t)(ptr) & MAXD_MASK] = delta; + /* Head of chain */ + hashtable[HASH_VALUE(ptr)] = (ptr) - base; + ptr++; + } while (ptr < end); + hc4->nexttoupdate = end; + } + + return (int)ml; +} + +static inline int lz4hc_insertandgetwidermatch(struct lz4hc_data *hc4, + const u8 *ip, const u8 *startlimit, const u8 *matchlimit, int longest, + const u8 **matchpos, const u8 **startpos) +{ + u16 *const chaintable = hc4->chaintable; + HTYPE *const hashtable = hc4->hashtable; +#if LZ4_ARCH64 + const BYTE * const base = hc4->base; +#else + const int base = 0; +#endif + const u8 *ref; + int nbattempts = MAX_NB_ATTEMPTS; + int delta = (int)(ip - startlimit); + + /* First Match */ + lz4hc_insert(hc4, ip); + ref = hashtable[HASH_VALUE(ip)] + base; + + while ((ref >= ip - MAX_DISTANCE) && (ref >= hc4->base) + && (nbattempts)) { + nbattempts--; + if (*(startlimit + longest) == *(ref - delta + longest)) { + if (A32(ref) == A32(ip)) { + const u8 *reft = ref + MINMATCH; + const u8 *ipt = ip + MINMATCH; + const u8 *startt = ip; + + while (ipt < matchlimit-(STEPSIZE - 1)) { + #if LZ4_ARCH64 + u64 diff = A64(reft) ^ A64(ipt); + #else + u32 diff = A32(reft) ^ A32(ipt); + #endif + + if (!diff) { + ipt += STEPSIZE; + reft += STEPSIZE; + continue; + } + ipt += LZ4_NBCOMMONBYTES(diff); + goto _endcount; + } + #if LZ4_ARCH64 + if ((ipt < (matchlimit - 3)) + && (A32(reft) == A32(ipt))) { + ipt += 4; + reft += 4; + } + ipt += 2; + #endif + if ((ipt < (matchlimit - 1)) + && (A16(reft) == A16(ipt))) { + reft += 2; + } + if ((ipt < matchlimit) && (*reft == *ipt)) + ipt++; +_endcount: + reft = ref; + + while ((startt > startlimit) + && (reft > hc4->base) + && (startt[-1] == reft[-1])) { + startt--; + reft--; + } + + if ((ipt - startt) > longest) { + longest = (int)(ipt - startt); + *matchpos = reft; + *startpos = startt; + } + } + } + ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK]; + } + return longest; +} + +static inline int lz4_encodesequence(const u8 **ip, u8 **op, const u8 **anchor, + int ml, const u8 *ref) +{ + int length, len; + u8 *token; + + /* Encode Literal length */ + length = (int)(*ip - *anchor); + token = (*op)++; + if (length >= (int)RUN_MASK) { + *token = (RUN_MASK << ML_BITS); + len = length - RUN_MASK; + for (; len > 254 ; len -= 255) + *(*op)++ = 255; + *(*op)++ = (u8)len; + } else + *token = (length << ML_BITS); + + /* Copy Literals */ + LZ4_BLINDCOPY(*anchor, *op, length); + + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(*op, (u16)(*ip - ref)); + + /* Encode MatchLength */ + len = (int)(ml - MINMATCH); + if (len >= (int)ML_MASK) { + *token += ML_MASK; + len -= ML_MASK; + for (; len > 509 ; len -= 510) { + *(*op)++ = 255; + *(*op)++ = 255; + } + if (len > 254) { + len -= 255; + *(*op)++ = 255; + } + *(*op)++ = (u8)len; + } else + *token += len; + + /* Prepare next loop */ + *ip += ml; + *anchor = *ip; + + return 0; +} + +static int lz4_compresshcctx(struct lz4hc_data *ctx, + const char *source, + char *dest, + int isize) +{ + const u8 *ip = (const u8 *)source; + const u8 *anchor = ip; + const u8 *const iend = ip + isize; + const u8 *const mflimit = iend - MFLIMIT; + const u8 *const matchlimit = (iend - LASTLITERALS); + + u8 *op = (u8 *)dest; + + int ml, ml2, ml3, ml0; + const u8 *ref = NULL; + const u8 *start2 = NULL; + const u8 *ref2 = NULL; + const u8 *start3 = NULL; + const u8 *ref3 = NULL; + const u8 *start0; + const u8 *ref0; + int lastrun; + + ip++; + + /* Main Loop */ + while (ip < mflimit) { + ml = lz4hc_insertandfindbestmatch(ctx, ip, matchlimit, (&ref)); + if (!ml) { + ip++; + continue; + } + + /* saved, in case we would skip too much */ + start0 = ip; + ref0 = ref; + ml0 = ml; +_search2: + if (ip+ml < mflimit) + ml2 = lz4hc_insertandgetwidermatch(ctx, ip + ml - 2, + ip + 1, matchlimit, ml, &ref2, &start2); + else + ml2 = ml; + /* No better match */ + if (ml2 == ml) { + lz4_encodesequence(&ip, &op, &anchor, ml, ref); + continue; + } + + if (start0 < ip) { + /* empirical */ + if (start2 < ip + ml0) { + ip = start0; + ref = ref0; + ml = ml0; + } + } + /* + * Here, start0==ip + * First Match too small : removed + */ + if ((start2 - ip) < 3) { + ml = ml2; + ip = start2; + ref = ref2; + goto _search2; + } + +_search3: + /* + * Currently we have : + * ml2 > ml1, and + * ip1+3 <= ip2 (usually < ip1+ml1) + */ + if ((start2 - ip) < OPTIMAL_ML) { + int correction; + int new_ml = ml; + if (new_ml > OPTIMAL_ML) + new_ml = OPTIMAL_ML; + if (ip + new_ml > start2 + ml2 - MINMATCH) + new_ml = (int)(start2 - ip) + ml2 - MINMATCH; + correction = new_ml - (int)(start2 - ip); + if (correction > 0) { + start2 += correction; + ref2 += correction; + ml2 -= correction; + } + } + /* + * Now, we have start2 = ip+new_ml, + * with new_ml=min(ml, OPTIMAL_ML=18) + */ + if (start2 + ml2 < mflimit) + ml3 = lz4hc_insertandgetwidermatch(ctx, + start2 + ml2 - 3, start2, matchlimit, + ml2, &ref3, &start3); + else + ml3 = ml2; + + /* No better match : 2 sequences to encode */ + if (ml3 == ml2) { + /* ip & ref are known; Now for ml */ + if (start2 < ip+ml) + ml = (int)(start2 - ip); + + /* Now, encode 2 sequences */ + lz4_encodesequence(&ip, &op, &anchor, ml, ref); + ip = start2; + lz4_encodesequence(&ip, &op, &anchor, ml2, ref2); + continue; + } + + /* Not enough space for match 2 : remove it */ + if (start3 < ip + ml + 3) { + /* + * can write Seq1 immediately ==> Seq2 is removed, + * so Seq3 becomes Seq1 + */ + if (start3 >= (ip + ml)) { + if (start2 < ip + ml) { + int correction = + (int)(ip + ml - start2); + start2 += correction; + ref2 += correction; + ml2 -= correction; + if (ml2 < MINMATCH) { + start2 = start3; + ref2 = ref3; + ml2 = ml3; + } + } + + lz4_encodesequence(&ip, &op, &anchor, ml, ref); + ip = start3; + ref = ref3; + ml = ml3; + + start0 = start2; + ref0 = ref2; + ml0 = ml2; + goto _search2; + } + + start2 = start3; + ref2 = ref3; + ml2 = ml3; + goto _search3; + } + + /* + * OK, now we have 3 ascending matches; let's write at least + * the first one ip & ref are known; Now for ml + */ + if (start2 < ip + ml) { + if ((start2 - ip) < (int)ML_MASK) { + int correction; + if (ml > OPTIMAL_ML) + ml = OPTIMAL_ML; + if (ip + ml > start2 + ml2 - MINMATCH) + ml = (int)(start2 - ip) + ml2 + - MINMATCH; + correction = ml - (int)(start2 - ip); + if (correction > 0) { + start2 += correction; + ref2 += correction; + ml2 -= correction; + } + } else + ml = (int)(start2 - ip); + } + lz4_encodesequence(&ip, &op, &anchor, ml, ref); + + ip = start2; + ref = ref2; + ml = ml2; + + start2 = start3; + ref2 = ref3; + ml2 = ml3; + + goto _search3; + } + + /* Encode Last Literals */ + lastrun = (int)(iend - anchor); + if (lastrun >= (int)RUN_MASK) { + *op++ = (RUN_MASK << ML_BITS); + lastrun -= RUN_MASK; + for (; lastrun > 254 ; lastrun -= 255) + *op++ = 255; + *op++ = (u8) lastrun; + } else + *op++ = (lastrun << ML_BITS); + memcpy(op, anchor, iend - anchor); + op += iend - anchor; + /* End */ + return (int) (((char *)op) - dest); +} + +int lz4hc_compress(const unsigned char *src, size_t src_len, + unsigned char *dst, size_t *dst_len, void *wrkmem) +{ + int ret = -1; + int out_len = 0; + + struct lz4hc_data *hc4 = (struct lz4hc_data *)wrkmem; + lz4hc_init(hc4, (const u8 *)src); + out_len = lz4_compresshcctx((struct lz4hc_data *)hc4, (const u8 *)src, + (char *)dst, (int)src_len); + + if (out_len < 0) + goto exit; + + *dst_len = out_len; + return 0; + +exit: + return ret; +} +EXPORT_SYMBOL(lz4hc_compress); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("LZ4HC compressor");