The quilt patch titled
Subject: zram: add dictionary support to lz4hc
has been removed from the -mm tree. Its filename was
zram-add-dictionary-support-to-lz4hc.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: zram: add dictionary support to lz4hc
Date: Mon, 2 Sep 2024 19:56:09 +0900
Support pre-trained dictionary param. Just like lz4, lz4hc doesn't
mandate specific format of the dictionary and zstd --train can be used to
train a dictionary for lz4, according to [1].
TEST
====
*** lz4hc
/sys/block/zram0/mm_stat
1750638592 608954620 621031424 0 621031424 1 0 34288 34288
*** lz4hc dict=/etc/lz4-dict-amd64
/sys/block/zram0/mm_stat
1750671360 505068582 514994176 0 514994176 1 0 34278 34278
[1] https://github.com/lz4/lz4/issues/557
Link: https://lkml.kernel.org/r/20240902105656.1383858-22-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/backend_lz4hc.c | 75 ++++++++++++++++++++++++---
1 file changed, 68 insertions(+), 7 deletions(-)
--- a/drivers/block/zram/backend_lz4hc.c~zram-add-dictionary-support-to-lz4hc
+++ a/drivers/block/zram/backend_lz4hc.c
@@ -5,6 +5,13 @@
#include "backend_lz4hc.h"
+struct lz4hc_ctx {
+ void *mem;
+
+ LZ4_streamDecode_t *dstrm;
+ LZ4_streamHC_t *cstrm;
+};
+
static void lz4hc_release_params(struct zcomp_params *params)
{
}
@@ -19,25 +26,67 @@ static int lz4hc_setup_params(struct zco
static void lz4hc_destroy(struct zcomp_ctx *ctx)
{
- vfree(ctx->context);
+ struct lz4hc_ctx *zctx = ctx->context;
+
+ if (!zctx)
+ return;
+
+ kfree(zctx->dstrm);
+ kfree(zctx->cstrm);
+ vfree(zctx->mem);
+ kfree(zctx);
}
static int lz4hc_create(struct zcomp_params *params, struct zcomp_ctx *ctx)
{
- ctx->context = vmalloc(LZ4HC_MEM_COMPRESS);
- if (!ctx->context)
+ struct lz4hc_ctx *zctx;
+
+ zctx = kzalloc(sizeof(*zctx), GFP_KERNEL);
+ if (!zctx)
return -ENOMEM;
+ ctx->context = zctx;
+ if (params->dict_sz == 0) {
+ zctx->mem = vmalloc(LZ4HC_MEM_COMPRESS);
+ if (!zctx->mem)
+ goto error;
+ } else {
+ zctx->dstrm = kzalloc(sizeof(*zctx->dstrm), GFP_KERNEL);
+ if (!zctx->dstrm)
+ goto error;
+
+ zctx->cstrm = kzalloc(sizeof(*zctx->cstrm), GFP_KERNEL);
+ if (!zctx->cstrm)
+ goto error;
+ }
+
return 0;
+
+error:
+ lz4hc_destroy(ctx);
+ return -EINVAL;
}
static int lz4hc_compress(struct zcomp_params *params, struct zcomp_ctx *ctx,
struct zcomp_req *req)
{
+ struct lz4hc_ctx *zctx = ctx->context;
int ret;
- ret = LZ4_compress_HC(req->src, req->dst, req->src_len, req->dst_len,
- params->level, ctx->context);
+ if (!zctx->cstrm) {
+ ret = LZ4_compress_HC(req->src, req->dst, req->src_len,
+ req->dst_len, params->level,
+ zctx->mem);
+ } else {
+ /* Cstrm needs to be reset */
+ LZ4_resetStreamHC(zctx->cstrm, params->level);
+ ret = LZ4_loadDictHC(zctx->cstrm, params->dict,
+ params->dict_sz);
+ if (ret != params->dict_sz)
+ return -EINVAL;
+ ret = LZ4_compress_HC_continue(zctx->cstrm, req->src, req->dst,
+ req->src_len, req->dst_len);
+ }
if (!ret)
return -EINVAL;
req->dst_len = ret;
@@ -47,10 +96,22 @@ static int lz4hc_compress(struct zcomp_p
static int lz4hc_decompress(struct zcomp_params *params, struct zcomp_ctx *ctx,
struct zcomp_req *req)
{
+ struct lz4hc_ctx *zctx = ctx->context;
int ret;
- ret = LZ4_decompress_safe(req->src, req->dst, req->src_len,
- req->dst_len);
+ if (!zctx->dstrm) {
+ ret = LZ4_decompress_safe(req->src, req->dst, req->src_len,
+ req->dst_len);
+ } else {
+ /* Dstrm needs to be reset */
+ ret = LZ4_setStreamDecode(zctx->dstrm, params->dict,
+ params->dict_sz);
+ if (!ret)
+ return -EINVAL;
+ ret = LZ4_decompress_safe_continue(zctx->dstrm, req->src,
+ req->dst, req->src_len,
+ req->dst_len);
+ }
if (ret < 0)
return -EINVAL;
return 0;
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
zsmalloc-use-unique-zsmalloc-caches-names.patch
