Commit 239b7161 authored by Geliang Tang's avatar Geliang Tang Committed by Kees Cook
Browse files

pstore: Add lz4hc and 842 compression support 



Currently, pstore has supported three compression algorithms: zlib,
lzo and lz4. This patch added two more compression algorithms: lz4hc
and 842.

Signed-off-by: default avatarGeliang Tang <geliangtang@gmail.com>
[kees: tweaked Kconfig help text slightly]
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
parent 91ab883e

fs/pstore/Kconfig

+20 −0
Original line number Diff line number Diff line
@@ -19,6 +19,11 @@ choice 
        help

          This option chooses compression algorithm.



	  Currently, pstore has support for 5 compression algorithms:

	  zlib, lzo, lz4, lz4hc and 842.



	  The default compression algorithm is zlib.



config PSTORE_ZLIB_COMPRESS

        bool "ZLIB"

        select ZLIB_DEFLATE
@@ -39,6 +44,21 @@ config PSTORE_LZ4_COMPRESS 
        select LZ4_DECOMPRESS

        help

          This option enables LZ4 compression algorithm support.



config PSTORE_LZ4HC_COMPRESS

	bool "LZ4HC"

	select LZ4HC_COMPRESS

	select LZ4_DECOMPRESS

	help

	  This option enables LZ4HC (high compression) mode algorithm.



config PSTORE_842_COMPRESS

	bool "842"

	select 842_COMPRESS

	select 842_DECOMPRESS

	help

	  This option enables 842 compression algorithm support.



endchoice



config PSTORE_CONSOLE

fs/pstore/platform.c

+129 −18
Original line number Diff line number Diff line
@@ -34,9 +34,12 @@ 
#ifdef CONFIG_PSTORE_LZO_COMPRESS

#include <linux/lzo.h>

#endif

#ifdef CONFIG_PSTORE_LZ4_COMPRESS

#if defined(CONFIG_PSTORE_LZ4_COMPRESS) || defined(CONFIG_PSTORE_LZ4HC_COMPRESS)

#include <linux/lz4.h>

#endif

#ifdef CONFIG_PSTORE_842_COMPRESS

#include <linux/sw842.h>

#endif

#include <linux/string.h>

#include <linux/timer.h>

#include <linux/slab.h>
@@ -336,6 +339,33 @@ static const struct pstore_zbackend backend_lzo = { 
};

#endif



#if defined(CONFIG_PSTORE_LZ4_COMPRESS) || defined(CONFIG_PSTORE_LZ4HC_COMPRESS)

static int decompress_lz4(void *in, void *out, size_t inlen, size_t outlen)

{

	int ret;



	ret = LZ4_decompress_safe(in, out, inlen, outlen);

	if (ret < 0) {

		/*

		 * LZ4_decompress_safe will return an error code

		 * (< 0) if decompression failed

		 */

		pr_err("LZ4_decompress_safe error, ret = %d!\n", ret);

		return -EIO;

	}



	return ret;

}



static void free_lz4(void)

{

	kfree(workspace);

	kfree(big_oops_buf);

	big_oops_buf = NULL;

	big_oops_buf_sz = 0;

}

#endif



#ifdef CONFIG_PSTORE_LZ4_COMPRESS

static int compress_lz4(const void *in, void *out, size_t inlen, size_t outlen)

{
@@ -350,29 +380,54 @@ static int compress_lz4(const void *in, void *out, size_t inlen, size_t outlen) 
	return ret;

}



static int decompress_lz4(void *in, void *out, size_t inlen, size_t outlen)

static void allocate_lz4(void)

{

	big_oops_buf_sz = LZ4_compressBound(psinfo->bufsize);

	big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);

	if (big_oops_buf) {

		workspace = kmalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);

		if (!workspace) {

			pr_err("No memory for compression workspace; skipping compression\n");

			kfree(big_oops_buf);

			big_oops_buf = NULL;

		}

	} else {

		pr_err("No memory for uncompressed data; skipping compression\n");

		workspace = NULL;

	}

}



static const struct pstore_zbackend backend_lz4 = {

	.compress	= compress_lz4,

	.decompress	= decompress_lz4,

	.allocate	= allocate_lz4,

	.free		= free_lz4,

	.name		= "lz4",

};

#endif



#ifdef CONFIG_PSTORE_LZ4HC_COMPRESS

static int compress_lz4hc(const void *in, void *out,

			  size_t inlen, size_t outlen)

{

	int ret;



	ret = LZ4_decompress_safe(in, out, inlen, outlen);

	if (ret < 0) {

		/*

		 * LZ4_decompress_safe will return an error code

		 * (< 0) if decompression failed

		 */

		pr_err("LZ4_decompress_safe error, ret = %d!\n", ret);

	ret = LZ4_compress_HC(in, out, inlen, outlen,

			      LZ4HC_DEFAULT_CLEVEL, workspace);

	if (!ret) {

		pr_err("LZ4_compress_HC error; compression failed!\n");

		return -EIO;

	}



	return ret;

}



static void allocate_lz4(void)

static void allocate_lz4hc(void)

{

	big_oops_buf_sz = LZ4_compressBound(psinfo->bufsize);

	big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);

	if (big_oops_buf) {

		workspace = kmalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);

		workspace = kmalloc(LZ4HC_MEM_COMPRESS, GFP_KERNEL);

		if (!workspace) {

			pr_err("No memory for compression workspace; skipping compression\n");

			kfree(big_oops_buf);
@@ -384,7 +439,59 @@ static void allocate_lz4(void) 
	}

}



static void free_lz4(void)

static const struct pstore_zbackend backend_lz4hc = {

	.compress	= compress_lz4hc,

	.decompress	= decompress_lz4,

	.allocate	= allocate_lz4hc,

	.free		= free_lz4,

	.name		= "lz4hc",

};

#endif



#ifdef CONFIG_PSTORE_842_COMPRESS

static int compress_842(const void *in, void *out, size_t inlen, size_t outlen)

{

	int ret;



	ret = sw842_compress(in, inlen, out, (unsigned int *)&outlen, workspace);

	if (ret) {

		pr_err("sw842_compress error; compression failed!\n");

		return ret;

	}



	return outlen;

}



static int decompress_842(void *in, void *out, size_t inlen, size_t outlen)

{

	int ret;



	ret = sw842_decompress(in, inlen, out, (unsigned int *)&outlen);

	if (ret) {

		pr_err("sw842_decompress error, ret = %d!\n", ret);

		return ret;

	}



	return outlen;

}



static void allocate_842(void)

{

	big_oops_buf_sz = psinfo->bufsize;

	big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);

	if (big_oops_buf) {

		workspace = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL);

		if (!workspace) {

			kfree(big_oops_buf);

			big_oops_buf = NULL;

		}

	} else {

		pr_err("No memory for uncompressed data; skipping compression\n");

		workspace = NULL;

	}

}



static void free_842(void)

{

	kfree(workspace);

	kfree(big_oops_buf);
@@ -392,12 +499,12 @@ static void free_lz4(void) 
	big_oops_buf_sz = 0;

}



static const struct pstore_zbackend backend_lz4 = {

	.compress	= compress_lz4,

	.decompress	= decompress_lz4,

	.allocate	= allocate_lz4,

	.free		= free_lz4,

	.name		= "lz4",

static const struct pstore_zbackend backend_842 = {

	.compress	= compress_842,

	.decompress	= decompress_842,

	.allocate	= allocate_842,

	.free		= free_842,

	.name		= "842",

};

#endif
@@ -408,6 +515,10 @@ static const struct pstore_zbackend *zbackend = 
	&backend_lzo;

#elif defined(CONFIG_PSTORE_LZ4_COMPRESS)

	&backend_lz4;

#elif defined(CONFIG_PSTORE_LZ4HC_COMPRESS)

	&backend_lz4hc;

#elif defined(CONFIG_PSTORE_842_COMPRESS)

	&backend_842;

#else

	NULL;

#endif