recov_neon.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (C) 2012 Intel Corporation
 4 * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
 5 */
 6
 7#include <linux/raid/pq.h>
 8
 9#ifdef __KERNEL__
10#include <asm/simd.h>
11#include "neon.h"
12#else
13#define scoped_ksimd()
14#define cpu_has_neon()		(1)
15#endif
16
17static int raid6_has_neon(void)
18{
19	return cpu_has_neon();
20}
21
22static void raid6_2data_recov_neon(int disks, size_t bytes, int faila,
23		int failb, void **ptrs)
24{
25	u8 *p, *q, *dp, *dq;
26	const u8 *pbmul;	/* P multiplier table for B data */
27	const u8 *qmul;		/* Q multiplier table (for both) */
28
29	p = (u8 *)ptrs[disks - 2];
30	q = (u8 *)ptrs[disks - 1];
31
32	/*
33	 * Compute syndrome with zero for the missing data pages
34	 * Use the dead data pages as temporary storage for
35	 * delta p and delta q
36	 */
37	dp = (u8 *)ptrs[faila];
38	ptrs[faila] = raid6_get_zero_page();
39	ptrs[disks - 2] = dp;
40	dq = (u8 *)ptrs[failb];
41	ptrs[failb] = raid6_get_zero_page();
42	ptrs[disks - 1] = dq;
43
44	raid6_call.gen_syndrome(disks, bytes, ptrs);
45
46	/* Restore pointer table */
47	ptrs[faila]     = dp;
48	ptrs[failb]     = dq;
49	ptrs[disks - 2] = p;
50	ptrs[disks - 1] = q;
51
52	/* Now, pick the proper data tables */
53	pbmul = raid6_vgfmul[raid6_gfexi[failb-faila]];
54	qmul  = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila] ^
55					 raid6_gfexp[failb]]];
56
57	scoped_ksimd()
58		__raid6_2data_recov_neon(bytes, p, q, dp, dq, pbmul, qmul);
59}
60
61static void raid6_datap_recov_neon(int disks, size_t bytes, int faila,
62		void **ptrs)
63{
64	u8 *p, *q, *dq;
65	const u8 *qmul;		/* Q multiplier table */
66
67	p = (u8 *)ptrs[disks - 2];
68	q = (u8 *)ptrs[disks - 1];
69
70	/*
71	 * Compute syndrome with zero for the missing data page
72	 * Use the dead data page as temporary storage for delta q
73	 */
74	dq = (u8 *)ptrs[faila];
75	ptrs[faila] = raid6_get_zero_page();
76	ptrs[disks - 1] = dq;
77
78	raid6_call.gen_syndrome(disks, bytes, ptrs);
79
80	/* Restore pointer table */
81	ptrs[faila]     = dq;
82	ptrs[disks - 1] = q;
83
84	/* Now, pick the proper data tables */
85	qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila]]];
86
87	scoped_ksimd()
88		__raid6_datap_recov_neon(bytes, p, q, dq, qmul);
89}
90
91const struct raid6_recov_calls raid6_recov_neon = {
92	.data2		= raid6_2data_recov_neon,
93	.datap		= raid6_datap_recov_neon,
94	.valid		= raid6_has_neon,
95	.name		= "neon",
96	.priority	= 10,
97};