[PATCH v6 10/23] zram: add zlib compression backend support
From: Sergey Senozhatsky
Date: Fri Jul 12 2024 - 01:23:27 EST
Add s/w zlib (inflate/deflate) compression.
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
---
drivers/block/zram/Kconfig | 11 +++
drivers/block/zram/Makefile | 1 +
drivers/block/zram/backend_deflate.c | 132 +++++++++++++++++++++++++++
drivers/block/zram/backend_deflate.h | 10 ++
drivers/block/zram/zcomp.c | 4 +
5 files changed, 158 insertions(+)
create mode 100644 drivers/block/zram/backend_deflate.c
create mode 100644 drivers/block/zram/backend_deflate.h
diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig
index ee4fe2ee3413..bc3a1d0455b1 100644
--- a/drivers/block/zram/Kconfig
+++ b/drivers/block/zram/Kconfig
@@ -39,6 +39,12 @@ config ZRAM_BACKEND_ZSTD
select ZSTD_COMPRESS
select ZSTD_DECOMPRESS
+config ZRAM_BACKEND_DEFLATE
+ bool "deflate compression support"
+ depends on ZRAM
+ select ZLIB_DEFLATE
+ select ZLIB_INFLATE
+
choice
prompt "Default zram compressor"
default ZRAM_DEF_COMP_LZORLE
@@ -64,6 +70,10 @@ config ZRAM_DEF_COMP_ZSTD
bool "zstd"
depends on ZRAM_BACKEND_ZSTD
+config ZRAM_DEF_COMP_DEFLATE
+ bool "deflate"
+ depends on ZRAM_BACKEND_DEFLATE
+
endchoice
config ZRAM_DEF_COMP
@@ -73,6 +83,7 @@ config ZRAM_DEF_COMP
default "lz4" if ZRAM_DEF_COMP_LZ4
default "lz4hc" if ZRAM_DEF_COMP_LZ4HC
default "zstd" if ZRAM_DEF_COMP_ZSTD
+ default "deflate" if ZRAM_DEF_COMP_DEFLATE
default "unset-value"
config ZRAM_WRITEBACK
diff --git a/drivers/block/zram/Makefile b/drivers/block/zram/Makefile
index a2ca227e199c..266430548437 100644
--- a/drivers/block/zram/Makefile
+++ b/drivers/block/zram/Makefile
@@ -6,5 +6,6 @@ zram-$(CONFIG_ZRAM_BACKEND_LZO) += backend_lzorle.o backend_lzo.o
zram-$(CONFIG_ZRAM_BACKEND_LZ4) += backend_lz4.o
zram-$(CONFIG_ZRAM_BACKEND_LZ4HC) += backend_lz4hc.o
zram-$(CONFIG_ZRAM_BACKEND_ZSTD) += backend_zstd.o
+zram-$(CONFIG_ZRAM_BACKEND_DEFLATE) += backend_deflate.o
obj-$(CONFIG_ZRAM) += zram.o
diff --git a/drivers/block/zram/backend_deflate.c b/drivers/block/zram/backend_deflate.c
new file mode 100644
index 000000000000..acefb86701b9
--- /dev/null
+++ b/drivers/block/zram/backend_deflate.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/zlib.h>
+
+#include "backend_deflate.h"
+
+/* Use the same value as crypto API */
+#define DEFLATE_DEF_WINBITS 11
+#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
+
+struct deflate_ctx {
+ struct z_stream_s cctx;
+ struct z_stream_s dctx;
+ s32 level;
+};
+
+static void deflate_destroy(void *ctx)
+{
+ struct deflate_ctx *zctx = ctx;
+
+ if (zctx->cctx.workspace) {
+ zlib_deflateEnd(&zctx->cctx);
+ vfree(zctx->cctx.workspace);
+ }
+ if (zctx->dctx.workspace) {
+ zlib_inflateEnd(&zctx->dctx);
+ vfree(zctx->dctx.workspace);
+ }
+ kfree(zctx);
+}
+
+static void *deflate_create(void)
+{
+ struct deflate_ctx *ctx;
+ size_t sz;
+ int ret;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;
+
+ /* @FIXME: using a hardcoded Z_DEFAULT_COMPRESSION for now */
+ ctx->level = Z_DEFAULT_COMPRESSION;
+ sz = zlib_deflate_workspacesize(-DEFLATE_DEF_WINBITS, MAX_MEM_LEVEL);
+ ctx->cctx.workspace = vzalloc(sz);
+ if (!ctx->cctx.workspace)
+ goto error;
+
+ ret = zlib_deflateInit2(&ctx->cctx, ctx->level, Z_DEFLATED,
+ -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
+ Z_DEFAULT_STRATEGY);
+ if (ret != Z_OK)
+ goto error;
+
+ sz = zlib_inflate_workspacesize();
+ ctx->dctx.workspace = vzalloc(sz);
+ if (!ctx->dctx.workspace)
+ goto error;
+
+ ret = zlib_inflateInit2(&ctx->dctx, -DEFLATE_DEF_WINBITS);
+ if (ret != Z_OK)
+ goto error;
+
+ return ctx;
+
+error:
+ deflate_destroy(ctx);
+ return NULL;
+}
+
+static int deflate_compress(void *ctx, const unsigned char *src,
+ size_t src_len, unsigned char *dst,
+ size_t *dst_len)
+{
+ struct deflate_ctx *zctx = ctx;
+ struct z_stream_s *deflate;
+ int ret;
+
+ deflate = &zctx->cctx;
+ ret = zlib_deflateReset(deflate);
+ if (ret != Z_OK)
+ return -EINVAL;
+
+ deflate->next_in = (u8 *)src;
+ deflate->avail_in = src_len;
+ deflate->next_out = (u8 *)dst;
+ deflate->avail_out = *dst_len;
+
+ ret = zlib_deflate(deflate, Z_FINISH);
+ if (ret != Z_STREAM_END)
+ return -EINVAL;
+
+ *dst_len = deflate->total_out;
+ return 0;
+}
+
+static int deflate_decompress(void *ctx, const unsigned char *src,
+ size_t src_len, unsigned char *dst,
+ size_t dst_len)
+{
+ struct deflate_ctx *zctx = ctx;
+ struct z_stream_s *inflate;
+ int ret;
+
+ inflate = &zctx->dctx;
+
+ ret = zlib_inflateReset(inflate);
+ if (ret != Z_OK)
+ return -EINVAL;
+
+ inflate->next_in = (u8 *)src;
+ inflate->avail_in = src_len;
+ inflate->next_out = (u8 *)dst;
+ inflate->avail_out = dst_len;
+
+ ret = zlib_inflate(inflate, Z_SYNC_FLUSH);
+ if (ret != Z_STREAM_END)
+ return -EINVAL;
+
+ return 0;
+}
+
+const struct zcomp_ops backend_deflate = {
+ .compress = deflate_compress,
+ .decompress = deflate_decompress,
+ .create_ctx = deflate_create,
+ .destroy_ctx = deflate_destroy,
+ .name = "deflate",
+};
diff --git a/drivers/block/zram/backend_deflate.h b/drivers/block/zram/backend_deflate.h
new file mode 100644
index 000000000000..a39ac12b114c
--- /dev/null
+++ b/drivers/block/zram/backend_deflate.h
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#ifndef __BACKEND_DEFLATE_H__
+#define __BACKEND_DEFLATE_H__
+
+#include "zcomp.h"
+
+extern const struct zcomp_ops backend_deflate;
+
+#endif /* __BACKEND_DEFLATE_H__ */
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index b920462d7e56..4d212ef972ea 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -17,6 +17,7 @@
#include "backend_lz4.h"
#include "backend_lz4hc.h"
#include "backend_zstd.h"
+#include "backend_deflate.h"
static const struct zcomp_ops *backends[] = {
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZO)
@@ -31,6 +32,9 @@ static const struct zcomp_ops *backends[] = {
#endif
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_ZSTD)
&backend_zstd,
+#endif
+#if IS_ENABLED(CONFIG_ZRAM_BACKEND_DEFLATE)
+ &backend_deflate,
#endif
NULL
};
--
2.45.2.993.g49e7a77208-goog