zram: add 842 compression backend support

Add s/w 842 compression support.

Link: https://lkml.kernel.org/r/20240902105656.1383858-12-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>

diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig
index 9dedd2edfb285b15381f20f9b6e7560f9b5fd259..1e0e7e5910b83341fc3efbedd3f4ef94f17e4de8 100644 (file)
--- 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 26643054843741e8cd941500662985ce4a62f634..0fdefd576691bcbc9e667ce0355f91da3b2e6609 100644 (file)
--- a/drivers/block/zram/Makefile
+++ b/drivers/block/zram/Makefile
@@ -7,5 +7,6 @@ zram-$(CONFIG_ZRAM_BACKEND_LZ4)         += backend_lz4.o
 zram-$(CONFIG_ZRAM_BACKEND_LZ4HC)      += backend_lz4hc.o
 zram-$(CONFIG_ZRAM_BACKEND_ZSTD)       += backend_zstd.o
 zram-$(CONFIG_ZRAM_BACKEND_DEFLATE)    += backend_deflate.o
+zram-$(CONFIG_ZRAM_BACKEND_842)                += backend_842.o
 
 obj-$(CONFIG_ZRAM)     +=      zram.o

diff --git a/drivers/block/zram/backend_842.c b/drivers/block/zram/backend_842.c
new file mode 100644 (file)
index 0000000..005f3fc
--- /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, size_t src_len,
+                       unsigned char *dst, size_t *dst_len)
+{
+       struct sw842_ctx *zctx = ctx;
+       unsigned int dlen = *dst_len;
+       int ret;
+
+       ret = sw842_compress(src, src_len, 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, size_t dst_len)
+{
+       unsigned int dlen = dst_len;
+
+       return sw842_decompress(src, src_len, dst, &dlen);
+}
+
+const struct zcomp_ops 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 (file)
index 0000000..4dc85c1
--- /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 const struct zcomp_ops backend_842;
+
+#endif /* __BACKEND_842_H__ */

diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index d1396fe82b1db05c759f8b1abf04465d43df61c1..94e1c95032678fc3a6bbc8c7a440358f36a1a425 100644 (file)
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -18,6 +18,7 @@
 #include "backend_lz4hc.h"
 #include "backend_zstd.h"
 #include "backend_deflate.h"
+#include "backend_842.h"
 
 static const struct zcomp_ops *backends[] = {
 #if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZO)
@@ -35,6 +36,9 @@ static const struct zcomp_ops *backends[] = {
 #endif
 #if IS_ENABLED(CONFIG_ZRAM_BACKEND_DEFLATE)
        &backend_deflate,
+#endif
+#if IS_ENABLED(CONFIG_ZRAM_BACKEND_842)
+       &backend_842,
 #endif
        NULL
 };