tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2
3#include <linux/kernel.h>
4#include <linux/slab.h>
5#include <linux/vmalloc.h>
6#include <linux/zlib.h>
7
8#include "backend_deflate.h"
9
10/* Use the same value as crypto API */
11#define DEFLATE_DEF_WINBITS 11
12#define DEFLATE_DEF_MEMLEVEL MAX_MEM_LEVEL
13
14struct deflate_ctx {
15 struct z_stream_s cctx;
16 struct z_stream_s dctx;
17};
18
19static void deflate_release_params(struct zcomp_params *params)
20{
21}
22
23static int deflate_setup_params(struct zcomp_params *params)
24{
25 if (params->level == ZCOMP_PARAM_NO_LEVEL)
26 params->level = Z_DEFAULT_COMPRESSION;
27
28 return 0;
29}
30
31static void deflate_destroy(struct zcomp_ctx *ctx)
32{
33 struct deflate_ctx *zctx = ctx->context;
34
35 if (!zctx)
36 return;
37
38 if (zctx->cctx.workspace) {
39 zlib_deflateEnd(&zctx->cctx);
40 vfree(zctx->cctx.workspace);
41 }
42 if (zctx->dctx.workspace) {
43 zlib_inflateEnd(&zctx->dctx);
44 vfree(zctx->dctx.workspace);
45 }
46 kfree(zctx);
47}
48
49static int deflate_create(struct zcomp_params *params, struct zcomp_ctx *ctx)
50{
51 struct deflate_ctx *zctx;
52 size_t sz;
53 int ret;
54
55 zctx = kzalloc(sizeof(*zctx), GFP_KERNEL);
56 if (!zctx)
57 return -ENOMEM;
58
59 ctx->context = zctx;
60 sz = zlib_deflate_workspacesize(-DEFLATE_DEF_WINBITS, MAX_MEM_LEVEL);
61 zctx->cctx.workspace = vzalloc(sz);
62 if (!zctx->cctx.workspace)
63 goto error;
64
65 ret = zlib_deflateInit2(&zctx->cctx, params->level, Z_DEFLATED,
66 -DEFLATE_DEF_WINBITS, DEFLATE_DEF_MEMLEVEL,
67 Z_DEFAULT_STRATEGY);
68 if (ret != Z_OK)
69 goto error;
70
71 sz = zlib_inflate_workspacesize();
72 zctx->dctx.workspace = vzalloc(sz);
73 if (!zctx->dctx.workspace)
74 goto error;
75
76 ret = zlib_inflateInit2(&zctx->dctx, -DEFLATE_DEF_WINBITS);
77 if (ret != Z_OK)
78 goto error;
79
80 return 0;
81
82error:
83 deflate_destroy(ctx);
84 return -EINVAL;
85}
86
87static int deflate_compress(struct zcomp_params *params, struct zcomp_ctx *ctx,
88 struct zcomp_req *req)
89{
90 struct deflate_ctx *zctx = ctx->context;
91 struct z_stream_s *deflate;
92 int ret;
93
94 deflate = &zctx->cctx;
95 ret = zlib_deflateReset(deflate);
96 if (ret != Z_OK)
97 return -EINVAL;
98
99 deflate->next_in = (u8 *)req->src;
100 deflate->avail_in = req->src_len;
101 deflate->next_out = (u8 *)req->dst;
102 deflate->avail_out = req->dst_len;
103
104 ret = zlib_deflate(deflate, Z_FINISH);
105 if (ret != Z_STREAM_END)
106 return -EINVAL;
107
108 req->dst_len = deflate->total_out;
109 return 0;
110}
111
112static int deflate_decompress(struct zcomp_params *params,
113 struct zcomp_ctx *ctx,
114 struct zcomp_req *req)
115{
116 struct deflate_ctx *zctx = ctx->context;
117 struct z_stream_s *inflate;
118 int ret;
119
120 inflate = &zctx->dctx;
121
122 ret = zlib_inflateReset(inflate);
123 if (ret != Z_OK)
124 return -EINVAL;
125
126 inflate->next_in = (u8 *)req->src;
127 inflate->avail_in = req->src_len;
128 inflate->next_out = (u8 *)req->dst;
129 inflate->avail_out = req->dst_len;
130
131 ret = zlib_inflate(inflate, Z_SYNC_FLUSH);
132 if (ret != Z_STREAM_END)
133 return -EINVAL;
134
135 return 0;
136}
137
138const struct zcomp_ops backend_deflate = {
139 .compress = deflate_compress,
140 .decompress = deflate_decompress,
141 .create_ctx = deflate_create,
142 .destroy_ctx = deflate_destroy,
143 .setup_params = deflate_setup_params,
144 .release_params = deflate_release_params,
145 .name = "deflate",
146};