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/api.h>
17
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 /* Prototypes for functions in assembly files */
35 u32 crc32_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
36 u32 crc32_be_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
37 u32 crc32c_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
38
39 /*
40 * DEFINE_CRC32_VX() - Define a CRC-32 function using the vector extension
41 *
42 * Creates a function to perform a particular CRC-32 computation. Depending
43 * on the message buffer, the hardware-accelerated or software implementation
44 * is used. Note that the message buffer is aligned to improve fetch
45 * operations of VECTOR LOAD MULTIPLE instructions.
46 *
47 */
48 #define DEFINE_CRC32_VX(___fname, ___crc32_vx, ___crc32_sw) \
49 static u32 __pure ___fname(u32 crc, \
50 unsigned char const *data, size_t datalen) \
51 { \
52 struct kernel_fpu vxstate; \
53 unsigned long prealign, aligned, remaining; \
54 \
55 if (datalen < VX_MIN_LEN + VX_ALIGN_MASK) \
56 return ___crc32_sw(crc, data, datalen); \
57 \
58 if ((unsigned long)data & VX_ALIGN_MASK) { \
59 prealign = VX_ALIGNMENT - \
60 ((unsigned long)data & VX_ALIGN_MASK); \
61 datalen -= prealign; \
62 crc = ___crc32_sw(crc, data, prealign); \
63 data = (void *)((unsigned long)data + prealign); \
64 } \
65 \
66 aligned = datalen & ~VX_ALIGN_MASK; \
67 remaining = datalen & VX_ALIGN_MASK; \
68 \
69 kernel_fpu_begin(&vxstate, KERNEL_VXR_LOW); \
70 crc = ___crc32_vx(crc, data, aligned); \
71 kernel_fpu_end(&vxstate, KERNEL_VXR_LOW); \
72 \
73 if (remaining) \
74 crc = ___crc32_sw(crc, data + aligned, remaining); \
75 \
76 return crc; \
77 }
78
DEFINE_CRC32_VX(crc32_le_vx,crc32_le_vgfm_16,crc32_le)79 DEFINE_CRC32_VX(crc32_le_vx, crc32_le_vgfm_16, crc32_le)
80 DEFINE_CRC32_VX(crc32_be_vx, crc32_be_vgfm_16, crc32_be)
81 DEFINE_CRC32_VX(crc32c_le_vx, crc32c_le_vgfm_16, __crc32c_le)
82
83
84 static int crc32_vx_cra_init_zero(struct crypto_tfm *tfm)
85 {
86 struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
87
88 mctx->key = 0;
89 return 0;
90 }
91
crc32_vx_cra_init_invert(struct crypto_tfm * tfm)92 static int crc32_vx_cra_init_invert(struct crypto_tfm *tfm)
93 {
94 struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
95
96 mctx->key = ~0;
97 return 0;
98 }
99
crc32_vx_init(struct shash_desc * desc)100 static int crc32_vx_init(struct shash_desc *desc)
101 {
102 struct crc_ctx *mctx = crypto_shash_ctx(desc->tfm);
103 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
104
105 ctx->crc = mctx->key;
106 return 0;
107 }
108
crc32_vx_setkey(struct crypto_shash * tfm,const u8 * newkey,unsigned int newkeylen)109 static int crc32_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
110 unsigned int newkeylen)
111 {
112 struct crc_ctx *mctx = crypto_shash_ctx(tfm);
113
114 if (newkeylen != sizeof(mctx->key))
115 return -EINVAL;
116 mctx->key = le32_to_cpu(*(__le32 *)newkey);
117 return 0;
118 }
119
crc32be_vx_setkey(struct crypto_shash * tfm,const u8 * newkey,unsigned int newkeylen)120 static int crc32be_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
121 unsigned int newkeylen)
122 {
123 struct crc_ctx *mctx = crypto_shash_ctx(tfm);
124
125 if (newkeylen != sizeof(mctx->key))
126 return -EINVAL;
127 mctx->key = be32_to_cpu(*(__be32 *)newkey);
128 return 0;
129 }
130
crc32le_vx_final(struct shash_desc * desc,u8 * out)131 static int crc32le_vx_final(struct shash_desc *desc, u8 *out)
132 {
133 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
134
135 *(__le32 *)out = cpu_to_le32p(&ctx->crc);
136 return 0;
137 }
138
crc32be_vx_final(struct shash_desc * desc,u8 * out)139 static int crc32be_vx_final(struct shash_desc *desc, u8 *out)
140 {
141 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
142
143 *(__be32 *)out = cpu_to_be32p(&ctx->crc);
144 return 0;
145 }
146
crc32c_vx_final(struct shash_desc * desc,u8 * out)147 static int crc32c_vx_final(struct shash_desc *desc, u8 *out)
148 {
149 struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
150
151 /*
152 * Perform a final XOR with 0xFFFFFFFF to be in sync
153 * with the generic crc32c shash implementation.
154 */
155 *(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
156 return 0;
157 }
158
__crc32le_vx_finup(u32 * crc,const u8 * data,unsigned int len,u8 * out)159 static int __crc32le_vx_finup(u32 *crc, const u8 *data, unsigned int len,
160 u8 *out)
161 {
162 *(__le32 *)out = cpu_to_le32(crc32_le_vx(*crc, data, len));
163 return 0;
164 }
165
__crc32be_vx_finup(u32 * crc,const u8 * data,unsigned int len,u8 * out)166 static int __crc32be_vx_finup(u32 *crc, const u8 *data, unsigned int len,
167 u8 *out)
168 {
169 *(__be32 *)out = cpu_to_be32(crc32_be_vx(*crc, data, len));
170 return 0;
171 }
172
__crc32c_vx_finup(u32 * crc,const u8 * data,unsigned int len,u8 * out)173 static int __crc32c_vx_finup(u32 *crc, const u8 *data, unsigned int len,
174 u8 *out)
175 {
176 /*
177 * Perform a final XOR with 0xFFFFFFFF to be in sync
178 * with the generic crc32c shash implementation.
179 */
180 *(__le32 *)out = ~cpu_to_le32(crc32c_le_vx(*crc, data, len));
181 return 0;
182 }
183
184
185 #define CRC32_VX_FINUP(alg, func) \
186 static int alg ## _vx_finup(struct shash_desc *desc, const u8 *data, \
187 unsigned int datalen, u8 *out) \
188 { \
189 return __ ## alg ## _vx_finup(shash_desc_ctx(desc), \
190 data, datalen, out); \
191 }
192
193 CRC32_VX_FINUP(crc32le, crc32_le_vx)
194 CRC32_VX_FINUP(crc32be, crc32_be_vx)
195 CRC32_VX_FINUP(crc32c, crc32c_le_vx)
196
197 #define CRC32_VX_DIGEST(alg, func) \
198 static int alg ## _vx_digest(struct shash_desc *desc, const u8 *data, \
199 unsigned int len, u8 *out) \
200 { \
201 return __ ## alg ## _vx_finup(crypto_shash_ctx(desc->tfm), \
202 data, len, out); \
203 }
204
205 CRC32_VX_DIGEST(crc32le, crc32_le_vx)
206 CRC32_VX_DIGEST(crc32be, crc32_be_vx)
207 CRC32_VX_DIGEST(crc32c, crc32c_le_vx)
208
209 #define CRC32_VX_UPDATE(alg, func) \
210 static int alg ## _vx_update(struct shash_desc *desc, const u8 *data, \
211 unsigned int datalen) \
212 { \
213 struct crc_desc_ctx *ctx = shash_desc_ctx(desc); \
214 ctx->crc = func(ctx->crc, data, datalen); \
215 return 0; \
216 }
217
218 CRC32_VX_UPDATE(crc32le, crc32_le_vx)
219 CRC32_VX_UPDATE(crc32be, crc32_be_vx)
220 CRC32_VX_UPDATE(crc32c, crc32c_le_vx)
221
222
223 static struct shash_alg crc32_vx_algs[] = {
224 /* CRC-32 LE */
225 {
226 .init = crc32_vx_init,
227 .setkey = crc32_vx_setkey,
228 .update = crc32le_vx_update,
229 .final = crc32le_vx_final,
230 .finup = crc32le_vx_finup,
231 .digest = crc32le_vx_digest,
232 .descsize = sizeof(struct crc_desc_ctx),
233 .digestsize = CRC32_DIGEST_SIZE,
234 .base = {
235 .cra_name = "crc32",
236 .cra_driver_name = "crc32-vx",
237 .cra_priority = 200,
238 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
239 .cra_blocksize = CRC32_BLOCK_SIZE,
240 .cra_ctxsize = sizeof(struct crc_ctx),
241 .cra_module = THIS_MODULE,
242 .cra_init = crc32_vx_cra_init_zero,
243 },
244 },
245 /* CRC-32 BE */
246 {
247 .init = crc32_vx_init,
248 .setkey = crc32be_vx_setkey,
249 .update = crc32be_vx_update,
250 .final = crc32be_vx_final,
251 .finup = crc32be_vx_finup,
252 .digest = crc32be_vx_digest,
253 .descsize = sizeof(struct crc_desc_ctx),
254 .digestsize = CRC32_DIGEST_SIZE,
255 .base = {
256 .cra_name = "crc32be",
257 .cra_driver_name = "crc32be-vx",
258 .cra_priority = 200,
259 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
260 .cra_blocksize = CRC32_BLOCK_SIZE,
261 .cra_ctxsize = sizeof(struct crc_ctx),
262 .cra_module = THIS_MODULE,
263 .cra_init = crc32_vx_cra_init_zero,
264 },
265 },
266 /* CRC-32C LE */
267 {
268 .init = crc32_vx_init,
269 .setkey = crc32_vx_setkey,
270 .update = crc32c_vx_update,
271 .final = crc32c_vx_final,
272 .finup = crc32c_vx_finup,
273 .digest = crc32c_vx_digest,
274 .descsize = sizeof(struct crc_desc_ctx),
275 .digestsize = CRC32_DIGEST_SIZE,
276 .base = {
277 .cra_name = "crc32c",
278 .cra_driver_name = "crc32c-vx",
279 .cra_priority = 200,
280 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
281 .cra_blocksize = CRC32_BLOCK_SIZE,
282 .cra_ctxsize = sizeof(struct crc_ctx),
283 .cra_module = THIS_MODULE,
284 .cra_init = crc32_vx_cra_init_invert,
285 },
286 },
287 };
288
289
crc_vx_mod_init(void)290 static int __init crc_vx_mod_init(void)
291 {
292 return crypto_register_shashes(crc32_vx_algs,
293 ARRAY_SIZE(crc32_vx_algs));
294 }
295
crc_vx_mod_exit(void)296 static void __exit crc_vx_mod_exit(void)
297 {
298 crypto_unregister_shashes(crc32_vx_algs, ARRAY_SIZE(crc32_vx_algs));
299 }
300
301 module_cpu_feature_match(VXRS, crc_vx_mod_init);
302 module_exit(crc_vx_mod_exit);
303
304 MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");
305 MODULE_LICENSE("GPL");
306
307 MODULE_ALIAS_CRYPTO("crc32");
308 MODULE_ALIAS_CRYPTO("crc32-vx");
309 MODULE_ALIAS_CRYPTO("crc32c");
310 MODULE_ALIAS_CRYPTO("crc32c-vx");
311