1 // SPDX-License-Identifier: GPL-2.0-or-later 1
2 /*
3 * Calculate a CRC T10-DIF with vpmsum acceler
4 *
5 * Copyright 2017, Daniel Axtens, IBM Corporat
6 * [based on crc32c-vpmsum_glue.c]
7 */
8
9 #include <linux/crc-t10dif.h>
10 #include <crypto/internal/hash.h>
11 #include <crypto/internal/simd.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/string.h>
15 #include <linux/kernel.h>
16 #include <linux/cpufeature.h>
17 #include <asm/simd.h>
18 #include <asm/switch_to.h>
19
20 #define VMX_ALIGN 16
21 #define VMX_ALIGN_MASK (VMX_ALIGN-1)
22
23 #define VECTOR_BREAKPOINT 64
24
25 u32 __crct10dif_vpmsum(u32 crc, unsigned char
26
27 static u16 crct10dif_vpmsum(u16 crci, unsigned
28 {
29 unsigned int prealign;
30 unsigned int tail;
31 u32 crc = crci;
32
33 if (len < (VECTOR_BREAKPOINT + VMX_ALI
34 return crc_t10dif_generic(crc,
35
36 if ((unsigned long)p & VMX_ALIGN_MASK)
37 prealign = VMX_ALIGN - ((unsig
38 crc = crc_t10dif_generic(crc,
39 len -= prealign;
40 p += prealign;
41 }
42
43 if (len & ~VMX_ALIGN_MASK) {
44 crc <<= 16;
45 preempt_disable();
46 pagefault_disable();
47 enable_kernel_altivec();
48 crc = __crct10dif_vpmsum(crc,
49 disable_kernel_altivec();
50 pagefault_enable();
51 preempt_enable();
52 crc >>= 16;
53 }
54
55 tail = len & VMX_ALIGN_MASK;
56 if (tail) {
57 p += len & ~VMX_ALIGN_MASK;
58 crc = crc_t10dif_generic(crc,
59 }
60
61 return crc & 0xffff;
62 }
63
64 static int crct10dif_vpmsum_init(struct shash_
65 {
66 u16 *crc = shash_desc_ctx(desc);
67
68 *crc = 0;
69 return 0;
70 }
71
72 static int crct10dif_vpmsum_update(struct shas
73 unsigned int lengt
74 {
75 u16 *crc = shash_desc_ctx(desc);
76
77 *crc = crct10dif_vpmsum(*crc, data, le
78
79 return 0;
80 }
81
82
83 static int crct10dif_vpmsum_final(struct shash
84 {
85 u16 *crcp = shash_desc_ctx(desc);
86
87 *(u16 *)out = *crcp;
88 return 0;
89 }
90
91 static struct shash_alg alg = {
92 .init = crct10dif_vpmsum_ini
93 .update = crct10dif_vpmsum_upd
94 .final = crct10dif_vpmsum_fin
95 .descsize = CRC_T10DIF_DIGEST_SI
96 .digestsize = CRC_T10DIF_DIGEST_SI
97 .base = {
98 .cra_name = "crc
99 .cra_driver_name = "crc
100 .cra_priority = 200,
101 .cra_blocksize = CRC_
102 .cra_module = THIS
103 }
104 };
105
106 static int __init crct10dif_vpmsum_mod_init(vo
107 {
108 if (!cpu_has_feature(CPU_FTR_ARCH_207S
109 return -ENODEV;
110
111 return crypto_register_shash(&alg);
112 }
113
114 static void __exit crct10dif_vpmsum_mod_fini(v
115 {
116 crypto_unregister_shash(&alg);
117 }
118
119 module_cpu_feature_match(PPC_MODULE_FEATURE_VE
120 module_exit(crct10dif_vpmsum_mod_fini);
121
122 MODULE_AUTHOR("Daniel Axtens <dja@axtens.net>"
123 MODULE_DESCRIPTION("CRCT10DIF using vector pol
124 MODULE_LICENSE("GPL");
125 MODULE_ALIAS_CRYPTO("crct10dif");
126 MODULE_ALIAS_CRYPTO("crct10dif-vpmsum");
127
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