usercopy.c (7096B)
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 7unsigned 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} 76EXPORT_SYMBOL(raw_copy_from_user); 77 78unsigned 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} 143EXPORT_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 */ 156unsigned 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} 214EXPORT_SYMBOL(__clear_user);