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
14 struct deflate_ctx {
15 struct z_stream_s cctx;
16 struct z_stream_s dctx;
17 };
18
deflate_release_params(struct zcomp_params * params)19 static void deflate_release_params(struct zcomp_params *params)
20 {
21 }
22
deflate_setup_params(struct zcomp_params * params)23 static int deflate_setup_params(struct zcomp_params *params)
24 {
25 if (params->level == ZCOMP_PARAM_NOT_SET)
26 params->level = Z_DEFAULT_COMPRESSION;
27 if (params->deflate.winbits == ZCOMP_PARAM_NOT_SET)
28 params->deflate.winbits = DEFLATE_DEF_WINBITS;
29
30 return 0;
31 }
32
deflate_destroy(struct zcomp_ctx * ctx)33 static void deflate_destroy(struct zcomp_ctx *ctx)
34 {
35 struct deflate_ctx *zctx = ctx->context;
36
37 if (!zctx)
38 return;
39
40 if (zctx->cctx.workspace) {
41 zlib_deflateEnd(&zctx->cctx);
42 vfree(zctx->cctx.workspace);
43 }
44 if (zctx->dctx.workspace) {
45 zlib_inflateEnd(&zctx->dctx);
46 vfree(zctx->dctx.workspace);
47 }
48 kfree(zctx);
49 }
50
deflate_create(struct zcomp_params * params,struct zcomp_ctx * ctx)51 static int deflate_create(struct zcomp_params *params, struct zcomp_ctx *ctx)
52 {
53 struct deflate_ctx *zctx;
54 size_t sz;
55 int ret;
56
57 zctx = kzalloc(sizeof(*zctx), GFP_KERNEL);
58 if (!zctx)
59 return -ENOMEM;
60
61 ctx->context = zctx;
62 sz = zlib_deflate_workspacesize(params->deflate.winbits, MAX_MEM_LEVEL);
63 zctx->cctx.workspace = vzalloc(sz);
64 if (!zctx->cctx.workspace)
65 goto error;
66
67 ret = zlib_deflateInit2(&zctx->cctx, params->level, Z_DEFLATED,
68 params->deflate.winbits, DEFLATE_DEF_MEMLEVEL,
69 Z_DEFAULT_STRATEGY);
70 if (ret != Z_OK)
71 goto error;
72
73 sz = zlib_inflate_workspacesize();
74 zctx->dctx.workspace = vzalloc(sz);
75 if (!zctx->dctx.workspace)
76 goto error;
77
78 ret = zlib_inflateInit2(&zctx->dctx, params->deflate.winbits);
79 if (ret != Z_OK)
80 goto error;
81
82 return 0;
83
84 error:
85 deflate_destroy(ctx);
86 return -EINVAL;
87 }
88
deflate_compress(struct zcomp_params * params,struct zcomp_ctx * ctx,struct zcomp_req * req)89 static int deflate_compress(struct zcomp_params *params, struct zcomp_ctx *ctx,
90 struct zcomp_req *req)
91 {
92 struct deflate_ctx *zctx = ctx->context;
93 struct z_stream_s *deflate;
94 int ret;
95
96 deflate = &zctx->cctx;
97 ret = zlib_deflateReset(deflate);
98 if (ret != Z_OK)
99 return -EINVAL;
100
101 deflate->next_in = (u8 *)req->src;
102 deflate->avail_in = req->src_len;
103 deflate->next_out = (u8 *)req->dst;
104 deflate->avail_out = req->dst_len;
105
106 ret = zlib_deflate(deflate, Z_FINISH);
107 if (ret != Z_STREAM_END)
108 return -EINVAL;
109
110 req->dst_len = deflate->total_out;
111 return 0;
112 }
113
deflate_decompress(struct zcomp_params * params,struct zcomp_ctx * ctx,struct zcomp_req * req)114 static int deflate_decompress(struct zcomp_params *params,
115 struct zcomp_ctx *ctx,
116 struct zcomp_req *req)
117 {
118 struct deflate_ctx *zctx = ctx->context;
119 struct z_stream_s *inflate;
120 int ret;
121
122 inflate = &zctx->dctx;
123
124 ret = zlib_inflateReset(inflate);
125 if (ret != Z_OK)
126 return -EINVAL;
127
128 inflate->next_in = (u8 *)req->src;
129 inflate->avail_in = req->src_len;
130 inflate->next_out = (u8 *)req->dst;
131 inflate->avail_out = req->dst_len;
132
133 ret = zlib_inflate(inflate, Z_SYNC_FLUSH);
134 if (ret != Z_STREAM_END)
135 return -EINVAL;
136
137 return 0;
138 }
139
140 const struct zcomp_ops backend_deflate = {
141 .compress = deflate_compress,
142 .decompress = deflate_decompress,
143 .create_ctx = deflate_create,
144 .destroy_ctx = deflate_destroy,
145 .setup_params = deflate_setup_params,
146 .release_params = deflate_release_params,
147 .name = "deflate",
148 };
149