lib/raid6/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/neon.h>
  11 #else
  12 #define kernel_neon_begin()
  13 #define kernel_neon_end()
  14 #define cpu_has_neon()          (1)
  15 #endif
  16
  17 static int raid6_has_neon(void)
  18 {
  19         return cpu_has_neon();
  20 }
  21
  22 void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp,
  23                               uint8_t *dq, const uint8_t *pbmul,
  24                               const uint8_t *qmul);
  25
  26 void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq,
  27                               const uint8_t *qmul);
  28
  29 static void raid6_2data_recov_neon(int disks, size_t bytes, int faila,
  30                 int failb, void **ptrs)
  31 {
  32         u8 *p, *q, *dp, *dq;
  33         const u8 *pbmul;        /* P multiplier table for B data */
  34         const u8 *qmul;         /* Q multiplier table (for both) */
  35
  36         p = (u8 *)ptrs[disks - 2];
  37         q = (u8 *)ptrs[disks - 1];
  38
  39         /*
  40          * Compute syndrome with zero for the missing data pages
  41          * Use the dead data pages as temporary storage for
  42          * delta p and delta q
  43          */
  44         dp = (u8 *)ptrs[faila];
  45         ptrs[faila] = (void *)raid6_empty_zero_page;
  46         ptrs[disks - 2] = dp;
  47         dq = (u8 *)ptrs[failb];
  48         ptrs[failb] = (void *)raid6_empty_zero_page;
  49         ptrs[disks - 1] = dq;
  50
  51         raid6_call.gen_syndrome(disks, bytes, ptrs);
  52
  53         /* Restore pointer table */
  54         ptrs[faila]     = dp;
  55         ptrs[failb]     = dq;
  56         ptrs[disks - 2] = p;
  57         ptrs[disks - 1] = q;
  58
  59         /* Now, pick the proper data tables */
  60         pbmul = raid6_vgfmul[raid6_gfexi[failb-faila]];
  61         qmul  = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila] ^
  62                                          raid6_gfexp[failb]]];
  63
  64         kernel_neon_begin();
  65         __raid6_2data_recov_neon(bytes, p, q, dp, dq, pbmul, qmul);
  66         kernel_neon_end();
  67 }
  68
  69 static void raid6_datap_recov_neon(int disks, size_t bytes, int faila,
  70                 void **ptrs)
  71 {
  72         u8 *p, *q, *dq;
  73         const u8 *qmul;         /* Q multiplier table */
  74
  75         p = (u8 *)ptrs[disks - 2];
  76         q = (u8 *)ptrs[disks - 1];
  77
  78         /*
  79          * Compute syndrome with zero for the missing data page
  80          * Use the dead data page as temporary storage for delta q
  81          */
  82         dq = (u8 *)ptrs[faila];
  83         ptrs[faila] = (void *)raid6_empty_zero_page;
  84         ptrs[disks - 1] = dq;
  85
  86         raid6_call.gen_syndrome(disks, bytes, ptrs);
  87
  88         /* Restore pointer table */
  89         ptrs[faila]     = dq;
  90         ptrs[disks - 1] = q;
  91
  92         /* Now, pick the proper data tables */
  93         qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila]]];
  94
  95         kernel_neon_begin();
  96         __raid6_datap_recov_neon(bytes, p, q, dq, qmul);
  97         kernel_neon_end();
  98 }
  99
 100 const struct raid6_recov_calls raid6_recov_neon = {
 101         .data2          = raid6_2data_recov_neon,
 102         .datap          = raid6_datap_recov_neon,
 103         .valid          = raid6_has_neon,
 104         .name           = "neon",
 105         .priority       = 10,
 106 };