zram: add lz4hc compression backend support

Add s/w lz4hc compression support.

Link: https://lkml.kernel.org/r/20240902105656.1383858-8-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Sergey Senozhatsky 2024-09-02 19:55:55 +09:00 committed by Andrew Morton
parent 22d651c3b3
commit c60a4ef544
5 changed files with 100 additions and 2 deletions

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@ -26,6 +26,12 @@ config ZRAM_BACKEND_LZ4
select LZ4_COMPRESS
select LZ4_DECOMPRESS
config ZRAM_BACKEND_LZ4HC
bool "lz4hc compression support"
depends on ZRAM
select LZ4HC_COMPRESS
select LZ4_DECOMPRESS
choice
prompt "Default zram compressor"
default ZRAM_DEF_COMP_LZORLE
@ -43,6 +49,10 @@ config ZRAM_DEF_COMP_LZ4
bool "lz4"
depends on ZRAM_BACKEND_LZ4
config ZRAM_DEF_COMP_LZ4HC
bool "lz4hc"
depends on ZRAM_BACKEND_LZ4HC
endchoice
config ZRAM_DEF_COMP
@ -50,6 +60,7 @@ config ZRAM_DEF_COMP
default "lzo-rle" if ZRAM_DEF_COMP_LZORLE
default "lzo" if ZRAM_DEF_COMP_LZO
default "lz4" if ZRAM_DEF_COMP_LZ4
default "lz4hc" if ZRAM_DEF_COMP_LZ4HC
default "unset-value"
config ZRAM_WRITEBACK

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@ -2,7 +2,8 @@
zram-y := zcomp.o zram_drv.o
zram-$(CONFIG_ZRAM_BACKEND_LZO) += backend_lzorle.o backend_lzo.o
zram-$(CONFIG_ZRAM_BACKEND_LZ4) += backend_lz4.o
zram-$(CONFIG_ZRAM_BACKEND_LZO) += backend_lzorle.o backend_lzo.o
zram-$(CONFIG_ZRAM_BACKEND_LZ4) += backend_lz4.o
zram-$(CONFIG_ZRAM_BACKEND_LZ4HC) += backend_lz4hc.o
obj-$(CONFIG_ZRAM) += zram.o

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@ -0,0 +1,72 @@
#include <linux/kernel.h>
#include <linux/lz4.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "backend_lz4hc.h"
struct lz4hc_ctx {
void *mem;
s32 level;
};
static void lz4hc_destroy(void *ctx)
{
struct lz4hc_ctx *zctx = ctx;
vfree(zctx->mem);
kfree(zctx);
}
static void *lz4hc_create(void)
{
struct lz4hc_ctx *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return NULL;
/* @FIXME: using a hardcoded LZ4HC_DEFAULT_CLEVEL for now */
ctx->level = LZ4HC_DEFAULT_CLEVEL;
ctx->mem = vmalloc(LZ4HC_MEM_COMPRESS);
if (!ctx->mem)
goto error;
return ctx;
error:
lz4hc_destroy(ctx);
return NULL;
}
static int lz4hc_compress(void *ctx, const unsigned char *src, size_t src_len,
unsigned char *dst, size_t *dst_len)
{
struct lz4hc_ctx *zctx = ctx;
int ret;
ret = LZ4_compress_HC(src, dst, src_len, *dst_len,
zctx->level, zctx->mem);
if (!ret)
return -EINVAL;
*dst_len = ret;
return 0;
}
static int lz4hc_decompress(void *ctx, const unsigned char *src,
size_t src_len, unsigned char *dst, size_t dst_len)
{
int ret;
ret = LZ4_decompress_safe(src, dst, src_len, dst_len);
if (ret < 0)
return -EINVAL;
return 0;
}
const struct zcomp_ops backend_lz4hc = {
.compress = lz4hc_compress,
.decompress = lz4hc_decompress,
.create_ctx = lz4hc_create,
.destroy_ctx = lz4hc_destroy,
.name = "lz4hc",
};

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@ -0,0 +1,10 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#ifndef __BACKEND_LZ4HC_H__
#define __BACKEND_LZ4HC_H__
#include "zcomp.h"
extern const struct zcomp_ops backend_lz4hc;
#endif /* __BACKEND_LZ4HC_H__ */

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@ -15,6 +15,7 @@
#include "backend_lzo.h"
#include "backend_lzorle.h"
#include "backend_lz4.h"
#include "backend_lz4hc.h"
static const struct zcomp_ops *backends[] = {
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZO)
@ -23,6 +24,9 @@ static const struct zcomp_ops *backends[] = {
#endif
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZ4)
&backend_lz4,
#endif
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZ4HC)
&backend_lz4hc,
#endif
NULL
};