xref: /linux/lib/raid/raid6/riscv/recov_rvv.c (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2024 Institute of Software, CAS.
4  * Author: Chunyan Zhang <zhangchunyan@iscas.ac.cn>
5  */
6 
7 #include <linux/mm.h>
8 #include <linux/raid/pq.h>
9 #include "algos.h"
10 #include "rvv.h"
11 
12 static void __raid6_2data_recov_rvv(int bytes, u8 *p, u8 *q, u8 *dp,
13 				    u8 *dq, const u8 *pbmul,
14 				    const u8 *qmul)
15 {
16 	asm volatile (".option	push\n"
17 		      ".option	arch,+v\n"
18 		      "vsetvli	x0, %[avl], e8, m1, ta, ma\n"
19 		      ".option	pop\n"
20 		      : :
21 		      [avl]"r"(16)
22 	);
23 
24 	/*
25 	 * while ( bytes-- ) {
26 	 *	uint8_t px, qx, db;
27 	 *
28 	 *	px	  = *p ^ *dp;
29 	 *	qx	  = qmul[*q ^ *dq];
30 	 *	*dq++ = db = pbmul[px] ^ qx;
31 	 *	*dp++ = db ^ px;
32 	 *	p++; q++;
33 	 * }
34 	 */
35 	while (bytes) {
36 		/*
37 		 * v0:px, v1:dp,
38 		 * v2:qx, v3:dq,
39 		 * v4:vx, v5:vy,
40 		 * v6:qm0, v7:qm1,
41 		 * v8:pm0, v9:pm1,
42 		 * v14:p/qm[vx], v15:p/qm[vy]
43 		 */
44 		asm volatile (".option		push\n"
45 			      ".option		arch,+v\n"
46 			      "vle8.v		v0, (%[px])\n"
47 			      "vle8.v		v1, (%[dp])\n"
48 			      "vxor.vv		v0, v0, v1\n"
49 			      "vle8.v		v2, (%[qx])\n"
50 			      "vle8.v		v3, (%[dq])\n"
51 			      "vxor.vv		v4, v2, v3\n"
52 			      "vsrl.vi		v5, v4, 4\n"
53 			      "vand.vi		v4, v4, 0xf\n"
54 			      "vle8.v		v6, (%[qm0])\n"
55 			      "vle8.v		v7, (%[qm1])\n"
56 			      "vrgather.vv	v14, v6, v4\n" /* v14 = qm[vx] */
57 			      "vrgather.vv	v15, v7, v5\n" /* v15 = qm[vy] */
58 			      "vxor.vv		v2, v14, v15\n" /* v2 = qmul[*q ^ *dq] */
59 
60 			      "vsrl.vi		v5, v0, 4\n"
61 			      "vand.vi		v4, v0, 0xf\n"
62 			      "vle8.v		v8, (%[pm0])\n"
63 			      "vle8.v		v9, (%[pm1])\n"
64 			      "vrgather.vv	v14, v8, v4\n" /* v14 = pm[vx] */
65 			      "vrgather.vv	v15, v9, v5\n" /* v15 = pm[vy] */
66 			      "vxor.vv		v4, v14, v15\n" /* v4 = pbmul[px] */
67 			      "vxor.vv		v3, v4, v2\n" /* v3 = db = pbmul[px] ^ qx */
68 			      "vxor.vv		v1, v3, v0\n" /* v1 = db ^ px; */
69 			      "vse8.v		v3, (%[dq])\n"
70 			      "vse8.v		v1, (%[dp])\n"
71 			      ".option		pop\n"
72 			      : :
73 			      [px]"r"(p),
74 			      [dp]"r"(dp),
75 			      [qx]"r"(q),
76 			      [dq]"r"(dq),
77 			      [qm0]"r"(qmul),
78 			      [qm1]"r"(qmul + 16),
79 			      [pm0]"r"(pbmul),
80 			      [pm1]"r"(pbmul + 16)
81 			      :);
82 
83 		bytes -= 16;
84 		p += 16;
85 		q += 16;
86 		dp += 16;
87 		dq += 16;
88 	}
89 }
90 
91 static void __raid6_datap_recov_rvv(int bytes, u8 *p, u8 *q,
92 				    u8 *dq, const u8 *qmul)
93 {
94 	asm volatile (".option	push\n"
95 		      ".option	arch,+v\n"
96 		      "vsetvli	x0, %[avl], e8, m1, ta, ma\n"
97 		      ".option	pop\n"
98 		      : :
99 		      [avl]"r"(16)
100 	);
101 
102 	/*
103 	 * while (bytes--) {
104 	 *  *p++ ^= *dq = qmul[*q ^ *dq];
105 	 *  q++; dq++;
106 	 * }
107 	 */
108 	while (bytes) {
109 		/*
110 		 * v0:vx, v1:vy,
111 		 * v2:dq, v3:p,
112 		 * v4:qm0, v5:qm1,
113 		 * v10:m[vx], v11:m[vy]
114 		 */
115 		asm volatile (".option		push\n"
116 			      ".option		arch,+v\n"
117 			      "vle8.v		v0, (%[vx])\n"
118 			      "vle8.v		v2, (%[dq])\n"
119 			      "vxor.vv		v0, v0, v2\n"
120 			      "vsrl.vi		v1, v0, 4\n"
121 			      "vand.vi		v0, v0, 0xf\n"
122 			      "vle8.v		v4, (%[qm0])\n"
123 			      "vle8.v		v5, (%[qm1])\n"
124 			      "vrgather.vv	v10, v4, v0\n"
125 			      "vrgather.vv	v11, v5, v1\n"
126 			      "vxor.vv		v0, v10, v11\n"
127 			      "vle8.v		v1, (%[vy])\n"
128 			      "vxor.vv		v1, v0, v1\n"
129 			      "vse8.v		v0, (%[dq])\n"
130 			      "vse8.v		v1, (%[vy])\n"
131 			      ".option		pop\n"
132 			      : :
133 			      [vx]"r"(q),
134 			      [vy]"r"(p),
135 			      [dq]"r"(dq),
136 			      [qm0]"r"(qmul),
137 			      [qm1]"r"(qmul + 16)
138 			      :);
139 
140 		bytes -= 16;
141 		p += 16;
142 		q += 16;
143 		dq += 16;
144 	}
145 }
146 
147 static void raid6_2data_recov_rvv(int disks, size_t bytes, int faila,
148 				  int failb, void **ptrs)
149 {
150 	u8 *p, *q, *dp, *dq;
151 	const u8 *pbmul;	/* P multiplier table for B data */
152 	const u8 *qmul;		/* Q multiplier table (for both) */
153 
154 	p = (u8 *)ptrs[disks - 2];
155 	q = (u8 *)ptrs[disks - 1];
156 
157 	/*
158 	 * Compute syndrome with zero for the missing data pages
159 	 * Use the dead data pages as temporary storage for
160 	 * delta p and delta q
161 	 */
162 	dp = (u8 *)ptrs[faila];
163 	ptrs[faila] = page_address(ZERO_PAGE(0));
164 	ptrs[disks - 2] = dp;
165 	dq = (u8 *)ptrs[failb];
166 	ptrs[failb] = page_address(ZERO_PAGE(0));
167 	ptrs[disks - 1] = dq;
168 
169 	raid6_gen_syndrome(disks, bytes, ptrs);
170 
171 	/* Restore pointer table */
172 	ptrs[faila]     = dp;
173 	ptrs[failb]     = dq;
174 	ptrs[disks - 2] = p;
175 	ptrs[disks - 1] = q;
176 
177 	/* Now, pick the proper data tables */
178 	pbmul = raid6_vgfmul[raid6_gfexi[failb - faila]];
179 	qmul  = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila] ^
180 					 raid6_gfexp[failb]]];
181 
182 	kernel_vector_begin();
183 	__raid6_2data_recov_rvv(bytes, p, q, dp, dq, pbmul, qmul);
184 	kernel_vector_end();
185 }
186 
187 static void raid6_datap_recov_rvv(int disks, size_t bytes, int faila,
188 				  void **ptrs)
189 {
190 	u8 *p, *q, *dq;
191 	const u8 *qmul;		/* Q multiplier table */
192 
193 	p = (u8 *)ptrs[disks - 2];
194 	q = (u8 *)ptrs[disks - 1];
195 
196 	/*
197 	 * Compute syndrome with zero for the missing data page
198 	 * Use the dead data page as temporary storage for delta q
199 	 */
200 	dq = (u8 *)ptrs[faila];
201 	ptrs[faila] = page_address(ZERO_PAGE(0));
202 	ptrs[disks - 1] = dq;
203 
204 	raid6_gen_syndrome(disks, bytes, ptrs);
205 
206 	/* Restore pointer table */
207 	ptrs[faila]     = dq;
208 	ptrs[disks - 1] = q;
209 
210 	/* Now, pick the proper data tables */
211 	qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila]]];
212 
213 	kernel_vector_begin();
214 	__raid6_datap_recov_rvv(bytes, p, q, dq, qmul);
215 	kernel_vector_end();
216 }
217 
218 const struct raid6_recov_calls raid6_recov_rvv = {
219 	.data2		= raid6_2data_recov_rvv,
220 	.datap		= raid6_datap_recov_rvv,
221 	.name		= "rvv",
222 };
223