1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Crypto-API module for CRC-32 algorithms implemented with the
4 * z/Architecture Vector Extension Facility.
5 *
6 * Copyright IBM Corp. 2015
7 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8 */
9 #define KMSG_COMPONENT "crc32-vx"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12 #include <linux/module.h>
13 #include <linux/cpufeature.h>
14 #include <linux/crc32.h>
15 #include <crypto/internal/hash.h>
16 #include <asm/fpu.h>
17 #include "crc32-vx.h"
18
19 #define CRC32_BLOCK_SIZE 1
20 #define CRC32_DIGEST_SIZE 4
21
22 #define VX_MIN_LEN 64
23 #define VX_ALIGNMENT 16L
24 #define VX_ALIGN_MASK (VX_ALIGNMENT - 1)
25
26 struct crc_ctx {
27 u32 key;
28 };
29
30 struct crc_desc_ctx {
31 u32 crc;
32 };
33
34 /*
35 * DEFINE_CRC32_VX() - Define a CRC-32 function using the vector extension
36 *
37 * Creates a function to perform a particular CRC-32 computation. Depending
38 * on the message buffer, the hardware-accelerated or software implementation
39 * is used. Note that the message buffer is aligned to improve fetch
40 * operations of VECTOR LOAD MULTIPLE instructions.
41 *
42 */
43 #define DEFINE_CRC32_VX(___fname, ___crc32_vx, ___crc32_sw) \
44 static u32 __pure ___fname(u32 crc, \
45 unsigned char const *data, size_t datalen) \
46 { \
47 unsigned long prealign, aligned, remaining; \
48 DECLARE_KERNEL_FPU_ONSTACK16(vxstate); \
49 \
50 if (datalen < VX_MIN_LEN + VX_ALIGN_MASK) \
51 return ___crc32_sw(crc, data, datalen); \
52 \
53 if ((unsigned long)data & VX_ALIGN_MASK) { \
54 prealign = VX_ALIGNMENT - \
55 ((unsigned long)data & VX_ALIGN_MASK); \
56 datalen -= prealign; \
57 crc = ___crc32_sw(crc, data, prealign); \
58 data = (void *)((unsigned long)data + prealign); \
59 } \
60 \
61 aligned = datalen & ~VX_ALIGN_MASK; \
62 remaining = datalen & VX_ALIGN_MASK; \
63 \
64 kernel_fpu_begin(&vxstate, KERNEL_VXR_LOW); \
65 crc = ___crc32_vx(crc, data, aligned); \
66 kernel_fpu_end(&vxstate, KERNEL_VXR_LOW); \
67 \
68 if (remaining) \
69 crc = ___crc32_sw(crc, data + aligned, remaining); \
70 \
71 return crc; \
72 }
73
74 DEFINE_CRC32_VX(crc32_le_vx, crc32_le_vgfm_16, crc32_le)
75 DEFINE_CRC32_VX(crc32_be_vx, crc32_be_vgfm_16, crc32_be)
76 DEFINE_CRC32_VX(crc32c_le_vx, crc32c_le_vgfm_16, __crc32c_le)
77
78
79 static int crc32_vx_cra_init_zero(struct crypto_tfm *tfm)
80 {
81 struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
82
83 mctx->key = 0;
84 return 0;
85 }
86
87 static int crc32_vx_cra_init_invert(struct crypto_tfm *tfm)
88 {
89 struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
90
91 mctx->key = ~0;
92 return 0;
93 }
94
95 static int crc32_vx_init(struct shash_desc *desc)
96 {
97 struct crc_ctx *mctx = crypto_shash_ctx(desc->tfm);
98 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
99
100 ctx->crc = mctx->key;
101 return 0;
102 }
103
104 static int crc32_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
105 unsigned int newkeylen)
106 {
107 struct crc_ctx *mctx = crypto_shash_ctx(tfm);
108
109 if (newkeylen != sizeof(mctx->key))
110 return -EINVAL;
111 mctx->key = le32_to_cpu(*(__le32 *)newkey);
112 return 0;
113 }
114
115 static int crc32be_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
116 unsigned int newkeylen)
117 {
118 struct crc_ctx *mctx = crypto_shash_ctx(tfm);
119
120 if (newkeylen != sizeof(mctx->key))
121 return -EINVAL;
122 mctx->key = be32_to_cpu(*(__be32 *)newkey);
123 return 0;
124 }
125
126 static int crc32le_vx_final(struct shash_desc *desc, u8 *out)
127 {
128 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
129
130 *(__le32 *)out = cpu_to_le32p(&ctx->crc);
131 return 0;
132 }
133
134 static int crc32be_vx_final(struct shash_desc *desc, u8 *out)
135 {
136 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
137
138 *(__be32 *)out = cpu_to_be32p(&ctx->crc);
139 return 0;
140 }
141
142 static int crc32c_vx_final(struct shash_desc *desc, u8 *out)
143 {
144 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
145
146 /*
147 * Perform a final XOR with 0xFFFFFFFF to be in sync
148 * with the generic crc32c shash implementation.
149 */
150 *(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
151 return 0;
152 }
153
154 static int __crc32le_vx_finup(u32 *crc, const u8 *data, unsigned int len,
155 u8 *out)
156 {
157 *(__le32 *)out = cpu_to_le32(crc32_le_vx(*crc, data, len));
158 return 0;
159 }
160
161 static int __crc32be_vx_finup(u32 *crc, const u8 *data, unsigned int len,
162 u8 *out)
163 {
164 *(__be32 *)out = cpu_to_be32(crc32_be_vx(*crc, data, len));
165 return 0;
166 }
167
168 static int __crc32c_vx_finup(u32 *crc, const u8 *data, unsigned int len,
169 u8 *out)
170 {
171 /*
172 * Perform a final XOR with 0xFFFFFFFF to be in sync
173 * with the generic crc32c shash implementation.
174 */
175 *(__le32 *)out = ~cpu_to_le32(crc32c_le_vx(*crc, data, len));
176 return 0;
177 }
178
179
180 #define CRC32_VX_FINUP(alg, func) \
181 static int alg ## _vx_finup(struct shash_desc *desc, const u8 *data, \
182 unsigned int datalen, u8 *out) \
183 { \
184 return __ ## alg ## _vx_finup(shash_desc_ctx(desc), \
185 data, datalen, out); \
186 }
187
188 CRC32_VX_FINUP(crc32le, crc32_le_vx)
189 CRC32_VX_FINUP(crc32be, crc32_be_vx)
190 CRC32_VX_FINUP(crc32c, crc32c_le_vx)
191
192 #define CRC32_VX_DIGEST(alg, func) \
193 static int alg ## _vx_digest(struct shash_desc *desc, const u8 *data, \
194 unsigned int len, u8 *out) \
195 { \
196 return __ ## alg ## _vx_finup(crypto_shash_ctx(desc->tfm), \
197 data, len, out); \
198 }
199
200 CRC32_VX_DIGEST(crc32le, crc32_le_vx)
201 CRC32_VX_DIGEST(crc32be, crc32_be_vx)
202 CRC32_VX_DIGEST(crc32c, crc32c_le_vx)
203
204 #define CRC32_VX_UPDATE(alg, func) \
205 static int alg ## _vx_update(struct shash_desc *desc, const u8 *data, \
206 unsigned int datalen) \
207 { \
208 struct crc_desc_ctx *ctx = shash_desc_ctx(desc); \
209 ctx->crc = func(ctx->crc, data, datalen); \
210 return 0; \
211 }
212
213 CRC32_VX_UPDATE(crc32le, crc32_le_vx)
214 CRC32_VX_UPDATE(crc32be, crc32_be_vx)
215 CRC32_VX_UPDATE(crc32c, crc32c_le_vx)
216
217
218 static struct shash_alg crc32_vx_algs[] = {
219 /* CRC-32 LE */
220 {
221 .init = crc32_vx_init,
222 .setkey = crc32_vx_setkey,
223 .update = crc32le_vx_update,
224 .final = crc32le_vx_final,
225 .finup = crc32le_vx_finup,
226 .digest = crc32le_vx_digest,
227 .descsize = sizeof(struct crc_desc_ctx),
228 .digestsize = CRC32_DIGEST_SIZE,
229 .base = {
230 .cra_name = "crc32",
231 .cra_driver_name = "crc32-vx",
232 .cra_priority = 200,
233 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
234 .cra_blocksize = CRC32_BLOCK_SIZE,
235 .cra_ctxsize = sizeof(struct crc_ctx),
236 .cra_module = THIS_MODULE,
237 .cra_init = crc32_vx_cra_init_zero,
238 },
239 },
240 /* CRC-32 BE */
241 {
242 .init = crc32_vx_init,
243 .setkey = crc32be_vx_setkey,
244 .update = crc32be_vx_update,
245 .final = crc32be_vx_final,
246 .finup = crc32be_vx_finup,
247 .digest = crc32be_vx_digest,
248 .descsize = sizeof(struct crc_desc_ctx),
249 .digestsize = CRC32_DIGEST_SIZE,
250 .base = {
251 .cra_name = "crc32be",
252 .cra_driver_name = "crc32be-vx",
253 .cra_priority = 200,
254 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
255 .cra_blocksize = CRC32_BLOCK_SIZE,
256 .cra_ctxsize = sizeof(struct crc_ctx),
257 .cra_module = THIS_MODULE,
258 .cra_init = crc32_vx_cra_init_zero,
259 },
260 },
261 /* CRC-32C LE */
262 {
263 .init = crc32_vx_init,
264 .setkey = crc32_vx_setkey,
265 .update = crc32c_vx_update,
266 .final = crc32c_vx_final,
267 .finup = crc32c_vx_finup,
268 .digest = crc32c_vx_digest,
269 .descsize = sizeof(struct crc_desc_ctx),
270 .digestsize = CRC32_DIGEST_SIZE,
271 .base = {
272 .cra_name = "crc32c",
273 .cra_driver_name = "crc32c-vx",
274 .cra_priority = 200,
275 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
276 .cra_blocksize = CRC32_BLOCK_SIZE,
277 .cra_ctxsize = sizeof(struct crc_ctx),
278 .cra_module = THIS_MODULE,
279 .cra_init = crc32_vx_cra_init_invert,
280 },
281 },
282 };
283
284
285 static int __init crc_vx_mod_init(void)
286 {
287 return crypto_register_shashes(crc32_vx_algs,
288 ARRAY_SIZE(crc32_vx_algs));
289 }
290
291 static void __exit crc_vx_mod_exit(void)
292 {
293 crypto_unregister_shashes(crc32_vx_algs, ARRAY_SIZE(crc32_vx_algs));
294 }
295
296 module_cpu_feature_match(S390_CPU_FEATURE_VXRS, crc_vx_mod_init);
297 module_exit(crc_vx_mod_exit);
298
299 MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");
300 MODULE_DESCRIPTION("CRC-32 algorithms using z/Architecture Vector Extension Facility");
301 MODULE_LICENSE("GPL");
302
303 MODULE_ALIAS_CRYPTO("crc32");
304 MODULE_ALIAS_CRYPTO("crc32-vx");
305 MODULE_ALIAS_CRYPTO("crc32c");
306 MODULE_ALIAS_CRYPTO("crc32c-vx");
307
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