arch/csky/lib/usercopy.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
   3
   4 #include <linux/uaccess.h>
   5 #include <linux/types.h>
   6
   7 unsigned long raw_copy_from_user(void *to, const void *from,
   8                         unsigned long n)
   9 {
  10         int tmp, nsave;
  11
  12         __asm__ __volatile__(
  13         "0:     cmpnei  %1, 0           \n"
  14         "       bf      7f              \n"
  15         "       mov     %3, %1          \n"
  16         "       or      %3, %2          \n"
  17         "       andi    %3, 3           \n"
  18         "       cmpnei  %3, 0           \n"
  19         "       bf      1f              \n"
  20         "       br      5f              \n"
  21         "1:     cmplti  %0, 16          \n"
  22         "       bt      3f              \n"
  23         "2:     ldw     %3, (%2, 0)     \n"
  24         "10:    ldw     %4, (%2, 4)     \n"
  25         "       stw     %3, (%1, 0)     \n"
  26         "       stw     %4, (%1, 4)     \n"
  27         "11:    ldw     %3, (%2, 8)     \n"
  28         "12:    ldw     %4, (%2, 12)    \n"
  29         "       stw     %3, (%1, 8)     \n"
  30         "       stw     %4, (%1, 12)    \n"
  31         "       addi    %2, 16          \n"
  32         "       addi    %1, 16          \n"
  33         "       subi    %0, 16          \n"
  34         "       br      1b              \n"
  35         "3:     cmplti  %0, 4           \n"
  36         "       bt      5f              \n"
  37         "4:     ldw     %3, (%2, 0)     \n"
  38         "       stw     %3, (%1, 0)     \n"
  39         "       addi    %2, 4           \n"
  40         "       addi    %1, 4           \n"
  41         "       subi    %0, 4           \n"
  42         "       br      3b              \n"
  43         "5:     cmpnei  %0, 0           \n"
  44         "       bf      7f              \n"
  45         "6:     ldb     %3, (%2, 0)     \n"
  46         "       stb     %3, (%1, 0)     \n"
  47         "       addi    %2,  1          \n"
  48         "       addi    %1,  1          \n"
  49         "       subi    %0,  1          \n"
  50         "       br      5b              \n"
  51         "8:     stw     %3, (%1, 0)     \n"
  52         "       subi    %0, 4           \n"
  53         "       bf      7f              \n"
  54         "9:     subi    %0, 8           \n"
  55         "       bf      7f              \n"
  56         "13:    stw     %3, (%1, 8)     \n"
  57         "       subi    %0, 12          \n"
  58         "       bf      7f              \n"
  59         ".section __ex_table, \"a\"     \n"
  60         ".align   2                     \n"
  61         ".long    2b, 7f                \n"
  62         ".long    4b, 7f                \n"
  63         ".long    6b, 7f                \n"
  64         ".long   10b, 8b                \n"
  65         ".long   11b, 9b                \n"
  66         ".long   12b,13b                \n"
  67         ".previous                      \n"
  68         "7:                             \n"
  69         : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave),
  70           "=r"(tmp)
  71         : "0"(n), "1"(to), "2"(from)
  72         : "memory");
  73
  74         return n;
  75 }
  76 EXPORT_SYMBOL(raw_copy_from_user);
  77
  78 unsigned long raw_copy_to_user(void *to, const void *from,
  79                         unsigned long n)
  80 {
  81         int w0, w1, w2, w3;
  82
  83         __asm__ __volatile__(
  84         "0:     cmpnei  %1, 0           \n"
  85         "       bf      8f              \n"
  86         "       mov     %3, %1          \n"
  87         "       or      %3, %2          \n"
  88         "       andi    %3, 3           \n"
  89         "       cmpnei  %3, 0           \n"
  90         "       bf      1f              \n"
  91         "       br      5f              \n"
  92         "1:     cmplti  %0, 16          \n" /* 4W */
  93         "       bt      3f              \n"
  94         "       ldw     %3, (%2, 0)     \n"
  95         "       ldw     %4, (%2, 4)     \n"
  96         "       ldw     %5, (%2, 8)     \n"
  97         "       ldw     %6, (%2, 12)    \n"
  98         "2:     stw     %3, (%1, 0)     \n"
  99         "9:     stw     %4, (%1, 4)     \n"
 100         "10:    stw     %5, (%1, 8)     \n"
 101         "11:    stw     %6, (%1, 12)    \n"
 102         "       addi    %2, 16          \n"
 103         "       addi    %1, 16          \n"
 104         "       subi    %0, 16          \n"
 105         "       br      1b              \n"
 106         "3:     cmplti  %0, 4           \n" /* 1W */
 107         "       bt      5f              \n"
 108         "       ldw     %3, (%2, 0)     \n"
 109         "4:     stw     %3, (%1, 0)     \n"
 110         "       addi    %2, 4           \n"
 111         "       addi    %1, 4           \n"
 112         "       subi    %0, 4           \n"
 113         "       br      3b              \n"
 114         "5:     cmpnei  %0, 0           \n"  /* 1B */
 115         "       bf      13f             \n"
 116         "       ldb     %3, (%2, 0)     \n"
 117         "6:     stb     %3, (%1, 0)     \n"
 118         "       addi    %2,  1          \n"
 119         "       addi    %1,  1          \n"
 120         "       subi    %0,  1          \n"
 121         "       br      5b              \n"
 122         "7:     subi    %0,  4          \n"
 123         "8:     subi    %0,  4          \n"
 124         "12:    subi    %0,  4          \n"
 125         "       br      13f             \n"
 126         ".section __ex_table, \"a\"     \n"
 127         ".align   2                     \n"
 128         ".long    2b, 13f               \n"
 129         ".long    4b, 13f               \n"
 130         ".long    6b, 13f               \n"
 131         ".long    9b, 12b               \n"
 132         ".long   10b, 8b                \n"
 133         ".long   11b, 7b                \n"
 134         ".previous                      \n"
 135         "13:                            \n"
 136         : "=r"(n), "=r"(to), "=r"(from), "=r"(w0),
 137           "=r"(w1), "=r"(w2), "=r"(w3)
 138         : "0"(n), "1"(to), "2"(from)
 139         : "memory");
 140
 141         return n;
 142 }
 143 EXPORT_SYMBOL(raw_copy_to_user);
 144
 145 /*
 146  * __clear_user: - Zero a block of memory in user space, with less checking.
 147  * @to:   Destination address, in user space.
 148  * @n:    Number of bytes to zero.
 149  *
 150  * Zero a block of memory in user space.  Caller must check
 151  * the specified block with access_ok() before calling this function.
 152  *
 153  * Returns number of bytes that could not be cleared.
 154  * On success, this will be zero.
 155  */
 156 unsigned long
 157 __clear_user(void __user *to, unsigned long n)
 158 {
 159         int data, value, tmp;
 160
 161         __asm__ __volatile__(
 162         "0:     cmpnei  %1, 0           \n"
 163         "       bf      7f              \n"
 164         "       mov     %3, %1          \n"
 165         "       andi    %3, 3           \n"
 166         "       cmpnei  %3, 0           \n"
 167         "       bf      1f              \n"
 168         "       br      5f              \n"
 169         "1:     cmplti  %0, 32          \n" /* 4W */
 170         "       bt      3f              \n"
 171         "8:     stw     %2, (%1, 0)     \n"
 172         "10:    stw     %2, (%1, 4)     \n"
 173         "11:    stw     %2, (%1, 8)     \n"
 174         "12:    stw     %2, (%1, 12)    \n"
 175         "13:    stw     %2, (%1, 16)    \n"
 176         "14:    stw     %2, (%1, 20)    \n"
 177         "15:    stw     %2, (%1, 24)    \n"
 178         "16:    stw     %2, (%1, 28)    \n"
 179         "       addi    %1, 32          \n"
 180         "       subi    %0, 32          \n"
 181         "       br      1b              \n"
 182         "3:     cmplti  %0, 4           \n" /* 1W */
 183         "       bt      5f              \n"
 184         "4:     stw     %2, (%1, 0)     \n"
 185         "       addi    %1, 4           \n"
 186         "       subi    %0, 4           \n"
 187         "       br      3b              \n"
 188         "5:     cmpnei  %0, 0           \n" /* 1B */
 189         "9:     bf      7f              \n"
 190         "6:     stb     %2, (%1, 0)     \n"
 191         "       addi    %1,  1          \n"
 192         "       subi    %0,  1          \n"
 193         "       br      5b              \n"
 194         ".section __ex_table,\"a\"      \n"
 195         ".align   2                     \n"
 196         ".long    8b, 9b                \n"
 197         ".long    10b, 9b               \n"
 198         ".long    11b, 9b               \n"
 199         ".long    12b, 9b               \n"
 200         ".long    13b, 9b               \n"
 201         ".long    14b, 9b               \n"
 202         ".long    15b, 9b               \n"
 203         ".long    16b, 9b               \n"
 204         ".long    4b, 9b                \n"
 205         ".long    6b, 9b                \n"
 206         ".previous                      \n"
 207         "7:                             \n"
 208         : "=r"(n), "=r" (data), "=r"(value), "=r"(tmp)
 209         : "0"(n), "1"(to), "2"(0)
 210         : "memory");
 211
 212         return n;
 213 }
 214 EXPORT_SYMBOL(__clear_user);