LineageOS
diff --git a/‎include/linux/decompress/unlz4.h‎
Lines changed: 10 additions & 0 deletions b/‎include/linux/decompress/unlz4.h‎
Lines changed: 10 additions & 0 deletions
diff --git a/‎include/linux/lz4.h‎
Lines changed: 87 additions & 0 deletions b/‎include/linux/lz4.h‎
Lines changed: 87 additions & 0 deletions
diff --git a/‎init/Kconfig‎
Lines changed: 16 additions & 1 deletion b/‎init/Kconfig‎
Lines changed: 16 additions & 1 deletion
diff --git a/‎lib/Kconfig‎
Lines changed: 13 additions & 0 deletions b/‎lib/Kconfig‎
Lines changed: 13 additions & 0 deletions
diff --git a/‎lib/Makefile‎
Lines changed: 4 additions & 0 deletions b/‎lib/Makefile‎
Lines changed: 4 additions & 0 deletions
diff --git a/‎lib/decompress.c‎
Lines changed: 5 additions & 0 deletions b/‎lib/decompress.c‎
Lines changed: 5 additions & 0 deletions
diff --git a/‎lib/decompress_unlz4.c‎
Lines changed: 187 additions & 0 deletions b/‎lib/decompress_unlz4.c‎
Lines changed: 187 additions & 0 deletions
diff --git a/‎lib/lz4/Makefile‎
Lines changed: 3 additions & 0 deletions b/‎lib/lz4/Makefile‎
Lines changed: 3 additions & 0 deletions
@@ -0,0 +1,10 @@
+#ifndef DECOMPRESS_UNLZ4_H
+#define DECOMPRESS_UNLZ4_H
+
+int unlz4(unsigned char *inbuf, int len,
+	int(*fill)(void*, unsigned int),
+	int(*flush)(void*, unsigned int),
+	unsigned char *output,
+	int *pos,
+	void(*error)(char *x));
+#endif
@@ -0,0 +1,87 @@
+#ifndef __LZ4_H__
+#define __LZ4_H__
+/*
+ * LZ4 Kernel Interface
+ *
+ * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
+ *
+ * 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
@@ -98,10 +98,13 @@ config HAVE_KERNEL_XZ
 config HAVE_KERNEL_LZO
 	bool
 
+config HAVE_KERNEL_LZ4
+	bool
+
 choice
 	prompt "Kernel compression mode"
 	default KERNEL_GZIP
-	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO
+	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4
 	help
 	  The linux kernel is a kind of self-extracting executable.
 	  Several compression algorithms are available, which differ
@@ -168,6 +171,18 @@ config KERNEL_LZO
 	  size is about 10% bigger than gzip; however its speed
 	  (both compression and decompression) is the fastest.
 
+config KERNEL_LZ4
+	bool "LZ4"
+	depends on HAVE_KERNEL_LZ4
+	help
+	  LZ4 is an LZ77-type compressor with a fixed, byte-oriented encoding.
+	  A preliminary version of LZ4 de/compression tool is available at
+	  <https://code.google.com/p/lz4/>.
+
+	  Its compression ratio is worse than LZO. The size of the kernel
+	  is about 8% bigger than LZO. But the decompression speed is
+	  faster than LZO.
+
 endchoice
 
 config DEFAULT_HOSTNAME
 
@@ -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
 #
 
@@ -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/
 
@@ -84,6 +87,7 @@ lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
 lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
 lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
 lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
+lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
 
 obj-$(CONFIG_TEXTSEARCH) += textsearch.o
 obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
 
@@ -11,6 +11,7 @@
 #include <linux/decompress/unxz.h>
 #include <linux/decompress/inflate.h>
 #include <linux/decompress/unlzo.h>
+#include <linux/decompress/unlz4.h>
 
 #include <linux/types.h>
 #include <linux/string.h>
@@ -31,6 +32,9 @@
 #ifndef CONFIG_DECOMPRESS_LZO
 # define unlzo NULL
 #endif
+#ifndef CONFIG_DECOMPRESS_LZ4
+# define unlz4 NULL
+#endif
 
 struct compress_format {
 	unsigned char magic[2];
@@ -45,6 +49,7 @@ static const struct compress_format compressed_formats[] __initconst = {
 	{ {0x5d, 0x00}, "lzma", unlzma },
 	{ {0xfd, 0x37}, "xz", unxz },
 	{ {0x89, 0x4c}, "lzo", unlzo },
+	{ {0x02, 0x21}, "lz4", unlz4 },
 	{ {0, 0}, NULL, NULL }
 };
 
 
@@ -0,0 +1,187 @@
+/*
+ * Wrapper for decompressing LZ4-compressed kernel, initramfs, and initrd
+ *
+ * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
+ *
+ * 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.
+ */
+
+#ifdef STATIC
+#define PREBOOT
+#include "lz4/lz4_decompress.c"
+#else
+#include <linux/decompress/unlz4.h>
+#endif
+#include <linux/types.h>
+#include <linux/lz4.h>
+#include <linux/decompress/mm.h>
+#include <linux/compiler.h>
+
+#include <asm/unaligned.h>
+
+/*
+ * Note: Uncompressed chunk size is used in the compressor side
+ * (userspace side for compression).
+ * It is hardcoded because there is not proper way to extract it
+ * from the binary stream which is generated by the preliminary
+ * version of LZ4 tool so far.
+ */
+#define LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE (8 << 20)
+#define ARCHIVE_MAGICNUMBER 0x184C2102
+
+STATIC inline int INIT unlz4(u8 *input, int in_len,
+				int (*fill) (void *, unsigned int),
+				int (*flush) (void *, unsigned int),
+				u8 *output, int *posp,
+				void (*error) (char *x))
+{
+	int ret = -1;
+	size_t chunksize = 0;
+	size_t uncomp_chunksize = LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE;
+	u8 *inp;
+	u8 *inp_start;
+	u8 *outp;
+	int size = in_len;
+#ifdef PREBOOT
+	size_t out_len = get_unaligned_le32(input + in_len);
+#endif
+	size_t dest_len;
+
+
+	if (output) {
+		outp = output;
+	} else if (!flush) {
+		error("NULL output pointer and no flush function provided");
+		goto exit_0;
+	} else {
+		outp = large_malloc(uncomp_chunksize);
+		if (!outp) {
+			error("Could not allocate output buffer");
+			goto exit_0;
+		}
+	}
+
+	if (input && fill) {
+		error("Both input pointer and fill function provided,");
+		goto exit_1;
+	} else if (input) {
+		inp = input;
+	} else if (!fill) {
+		error("NULL input pointer and missing fill function");
+		goto exit_1;
+	} else {
+		inp = large_malloc(lz4_compressbound(uncomp_chunksize));
+		if (!inp) {
+			error("Could not allocate input buffer");
+			goto exit_1;
+		}
+	}
+	inp_start = inp;
+
+	if (posp)
+		*posp = 0;
+
+	if (fill)
+		fill(inp, 4);
+
+	chunksize = get_unaligned_le32(inp);
+	if (chunksize == ARCHIVE_MAGICNUMBER) {
+		inp += 4;
+		size -= 4;
+	} else {
+		error("invalid header");
+		goto exit_2;
+	}
+
+	if (posp)
+		*posp += 4;
+
+	for (;;) {
+
+		if (fill)
+			fill(inp, 4);
+
+		chunksize = get_unaligned_le32(inp);
+		if (chunksize == ARCHIVE_MAGICNUMBER) {
+			inp += 4;
+			size -= 4;
+			if (posp)
+				*posp += 4;
+			continue;
+		}
+		inp += 4;
+		size -= 4;
+
+		if (posp)
+			*posp += 4;
+
+		if (fill) {
+			if (chunksize > lz4_compressbound(uncomp_chunksize)) {
+				error("chunk length is longer than allocated");
+				goto exit_2;
+			}
+			fill(inp, chunksize);
+		}
+#ifdef PREBOOT
+		if (out_len >= uncomp_chunksize) {
+			dest_len = uncomp_chunksize;
+			out_len -= dest_len;
+		} else
+			dest_len = out_len;
+		ret = lz4_decompress(inp, &chunksize, outp, dest_len);
+#else
+		dest_len = uncomp_chunksize;
+		ret = lz4_decompress_unknownoutputsize(inp, chunksize, outp,
+				&dest_len);
+#endif
+		if (ret < 0) {
+			error("Decoding failed");
+			goto exit_2;
+		}
+
+		if (flush && flush(outp, dest_len) != dest_len)
+			goto exit_2;
+		if (output)
+			outp += dest_len;
+		if (posp)
+			*posp += chunksize;
+
+		size -= chunksize;
+
+		if (size == 0)
+			break;
+		else if (size < 0) {
+			error("data corrupted");
+			goto exit_2;
+		}
+
+		inp += chunksize;
+		if (fill)
+			inp = inp_start;
+	}
+
+	ret = 0;
+exit_2:
+	if (!input)
+		large_free(inp_start);
+exit_1:
+	if (!output)
+		large_free(outp);
+exit_0:
+	return ret;
+}
+
+#ifdef PREBOOT
+STATIC int INIT decompress(unsigned char *buf, int in_len,
+			      int(*fill)(void*, unsigned int),
+			      int(*flush)(void*, unsigned int),
+			      unsigned char *output,
+			      int *posp,
+			      void(*error)(char *x)
+	)
+{
+	return unlz4(buf, in_len - 4, fill, flush, output, posp, error);
+}
+#endif
@@ -0,0 +1,3 @@
+obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o
+obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o
+obj-$(CONFIG_LZ4_DECOMPRESS) += lz4_decompress.o
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+obj-$(CONFIG_LZ4_COMPRESS) += lz4_compress.o`
	`2`	`+obj-$(CONFIG_LZ4HC_COMPRESS) += lz4hc_compress.o`
	`3`	`+obj-$(CONFIG_LZ4_DECOMPRESS) += lz4_decompress.o`