The patch titled
Subject: zram: add zlib compression backend support
has been added to the -mm mm-unstable branch. Its filename is
zram-add-zlib-compression-backend-support.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-add-zlib-compression-backend-support.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: zram: add zlib compression backend support
Date: Wed, 15 May 2024 16:12:44 +0900
Add s/w zlib (inflate/deflate) compression.
Link: https://lkml.kernel.org/r/20240515071645.1788128-8-senozhatsky@xxxxxxxxxxxx
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nick Terrell <terrelln@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/block/zram/Kconfig | 11 ++
drivers/block/zram/Makefile | 1
drivers/block/zram/backend_deflate.c | 130 +++++++++++++++++++++++++
drivers/block/zram/backend_deflate.h | 10 +
drivers/block/zram/zcomp.c | 4
5 files changed, 156 insertions(+)
--- /dev/null
+++ a/drivers/block/zram/backend_deflate.c
@@ -0,0 +1,130 @@
+// 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,
+ 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 = PAGE_SIZE;
+ 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)
+{
+ 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 = PAGE_SIZE;
+
+ ret = zlib_inflate(inflate, Z_SYNC_FLUSH);
+ if (ret != Z_STREAM_END)
+ return -EINVAL;
+
+ return 0;
+}
+
+struct zcomp_backend backend_deflate = {
+ .compress = deflate_compress,
+ .decompress = deflate_decompress,
+ .create_ctx = deflate_create,
+ .destroy_ctx = deflate_destroy,
+ .name = "deflate",
+};
--- /dev/null
+++ a/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 struct zcomp_backend backend_deflate;
+
+#endif /* __BACKEND_DEFLATE_H__ */
--- a/drivers/block/zram/Kconfig~zram-add-zlib-compression-backend-support
+++ a/drivers/block/zram/Kconfig
@@ -38,6 +38,12 @@ 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
@@ -63,6 +69,10 @@ 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
@@ -72,6 +82,7 @@ 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
--- a/drivers/block/zram/Makefile~zram-add-zlib-compression-backend-support
+++ a/drivers/block/zram/Makefile
@@ -6,5 +6,6 @@ zram-$(CONFIG_ZRAM_BACKEND_LZO) += back
zram-$(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
--- a/drivers/block/zram/zcomp.c~zram-add-zlib-compression-backend-support
+++ a/drivers/block/zram/zcomp.c
@@ -20,6 +20,7 @@
#include "backend_lz4.h"
#include "backend_lz4hc.h"
#include "backend_zstd.h"
+#include "backend_deflate.h"
static struct zcomp_backend *backends[] = {
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_LZO)
@@ -35,6 +36,9 @@ static struct zcomp_backend *backends[]
#if IS_ENABLED(CONFIG_ZRAM_BACKEND_ZSTD)
&backend_zstd,
#endif
+#if IS_ENABLED(CONFIG_ZRAM_BACKEND_DEFLATE)
+ &backend_deflate,
+#endif
NULL
};
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
zram-move-from-crypto-api-to-custom-comp-backends-api.patch
zram-add-lzo-and-lzorle-compression-backends-support.patch
zram-add-lz4-compression-backend-support.patch
zram-add-lz4hc-compression-backend-support.patch
zram-add-zstd-compression-backend-support.patch
zram-pass-estimated-src-size-hint-to-zstd.patch
zram-add-zlib-compression-backend-support.patch
zram-add-842-compression-backend-support.patch
zram-check-that-backends-array-has-at-least-one-backend.patch
zram-introduce-zcomp_config-structure.patch
zram-extend-comp_algorithm-attr-write-handling.patch
zram-support-compression-level-comp-config.patch
zram-add-support-for-dict-comp-config.patch
lib-zstd-export-api-needed-for-dictionary-support.patch
zram-add-dictionary-support-to-zstd-backend.patch
zram-add-config-init-release-backend-callbacks.patch
zram-share-dictionaries-between-per-cpu-contexts.patch
zram-add-dictionary-support-to-lz4.patch
lib-lz4hc-export-lz4_resetstreamhc-symbol.patch
zram-add-dictionary-support-to-lz4hc.patch
documentation-zram-add-documentation-for-algorithm-parameters.patch
