[PATCHv2 08/17] zram: add 842 compression backend support

From: Sergey Senozhatsky
Date: Mon May 06 2024 - 04:00:53 EST


Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
---
drivers/block/zram/Kconfig | 11 ++++++
drivers/block/zram/Makefile | 1 +
drivers/block/zram/backend_842.c | 68 ++++++++++++++++++++++++++++++++
drivers/block/zram/backend_842.h | 10 +++++
drivers/block/zram/zcomp.c | 4 ++
5 files changed, 94 insertions(+)
create mode 100644 drivers/block/zram/backend_842.c
create mode 100644 drivers/block/zram/backend_842.h

diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig
index 9dedd2edfb28..1e0e7e5910b8 100644
--- a/drivers/block/zram/Kconfig
+++ b/drivers/block/zram/Kconfig
@@ -44,6 +44,12 @@ config ZRAM_BACKEND_DEFLATE
select ZLIB_DEFLATE
select ZLIB_INFLATE

+config ZRAM_BACKEND_842
+ bool "842 compression support"
+ depends on ZRAM
+ select 842_COMPRESS
+ select 842_DECOMPRESS
+
choice
prompt "Default zram compressor"
default ZRAM_DEF_COMP_LZORLE
@@ -73,6 +79,10 @@ config ZRAM_DEF_COMP_DEFLATE
bool "deflate"
depends on ZRAM_BACKEND_DEFLATE

+config ZRAM_DEF_COMP_842
+ bool "842"
+ depends on ZRAM_BACKEND_842
+
endchoice

config ZRAM_DEF_COMP
@@ -83,6 +93,7 @@ config ZRAM_DEF_COMP
default "lz4hc" if ZRAM_DEF_COMP_LZ4HC
default "zstd" if ZRAM_DEF_COMP_ZSTD
default "deflate" if ZRAM_DEF_COMP_DEFLATE
+ default "842" if ZRAM_DEF_COMP_842
default "unset-value"

config ZRAM_WRITEBACK
diff --git a/drivers/block/zram/Makefile b/drivers/block/zram/Makefile
index 91c07595d8b4..029827a6ddac 100644
--- a/drivers/block/zram/Makefile
+++ b/drivers/block/zram/Makefile
@@ -5,6 +5,7 @@ obj-$(CONFIG_ZRAM_BACKEND_LZ4) += backend_lz4.o
obj-$(CONFIG_ZRAM_BACKEND_LZ4HC) += backend_lz4hc.o
obj-$(CONFIG_ZRAM_BACKEND_ZSTD) += backend_zstd.o
obj-$(CONFIG_ZRAM_BACKEND_DEFLATE) += backend_deflate.o
+obj-$(CONFIG_ZRAM_BACKEND_842) += backend_842.o

zram-y := zcomp.o zram_drv.o

diff --git a/drivers/block/zram/backend_842.c b/drivers/block/zram/backend_842.c
new file mode 100644
index 000000000000..8ea7a230b890
--- /dev/null
+++ b/drivers/block/zram/backend_842.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sw842.h>
+#include <linux/vmalloc.h>
+
+#include "backend_842.h"
+
+struct sw842_ctx {
+ void *mem;
+};
+
+static void destroy_842(void *ctx)
+{
+ struct sw842_ctx *zctx = ctx;
+
+ kfree(zctx->mem);
+ kfree(zctx);
+}
+
+static void *create_842(void)
+{
+ struct sw842_ctx *ctx;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;
+
+ ctx->mem = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL);
+ if (!ctx->mem)
+ goto error;
+
+ return ctx;
+
+error:
+ destroy_842(ctx);
+ return NULL;
+}
+
+static int compress_842(void *ctx, const unsigned char *src,
+ unsigned char *dst, size_t *dst_len)
+{
+ struct sw842_ctx *zctx = ctx;
+ unsigned int dlen = *dst_len;
+ int ret;
+
+ ret = sw842_compress(src, PAGE_SIZE, dst, &dlen, zctx->mem);
+ if (ret == 0)
+ *dst_len = dlen;
+ return ret;
+}
+
+static int decompress_842(void *ctx, const unsigned char *src, size_t src_len,
+ unsigned char *dst)
+{
+ unsigned int dlen = PAGE_SIZE;
+
+ return sw842_decompress(src, src_len, dst, &dlen);
+}
+
+struct zcomp_backend backend_842 = {
+ .compress = compress_842,
+ .decompress = decompress_842,
+ .create_ctx = create_842,
+ .destroy_ctx = destroy_842,
+ .name = "842",
+};
diff --git a/drivers/block/zram/backend_842.h b/drivers/block/zram/backend_842.h
new file mode 100644
index 000000000000..c03a2396d7b2
--- /dev/null
+++ b/drivers/block/zram/backend_842.h
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#ifndef __BACKEND_842_H__
+#define __BACKEND_842_H__
+
+#include "zcomp.h"
+
+extern struct zcomp_backend backend_842;
+
+#endif /* __BACKEND_842_H__ */
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index 9fc5477a6259..2a38126f4da3 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -21,6 +21,7 @@
#include "backend_lz4hc.h"
#include "backend_zstd.h"
#include "backend_deflate.h"
+#include "backend_842.h"

static struct zcomp_backend *backends[] = {
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZO)
@@ -38,6 +39,9 @@ static struct zcomp_backend *backends[] = {
#endif
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_DEFLATE)
&backend_deflate,
+#endif
+#if IS_ENABLED(CONFIG_ZRAM_BACKEND_842)
+ &backend_842,
#endif
NULL
};
--
2.45.0.rc1.225.g2a3ae87e7f-goog