1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ALPHA_UACCESS_H 3 #define __ALPHA_UACCESS_H 4 5 #include <asm-generic/access_ok.h> 6 /* 7 * These are the main single-value transfer routines. They automatically 8 * use the right size if we just have the right pointer type. 9 * 10 * As the alpha uses the same address space for kernel and user 11 * data, we can just do these as direct assignments. (Of course, the 12 * exception handling means that it's no longer "just"...) 13 * 14 * Careful to not 15 * (a) re-use the arguments for side effects (sizeof/typeof is ok) 16 * (b) require any knowledge of processes at this stage 17 */ 18 #define put_user(x, ptr) \ 19 __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) 20 #define get_user(x, ptr) \ 21 __get_user_check((x), (ptr), sizeof(*(ptr))) 22 23 /* 24 * The "__xxx" versions do not do address space checking, useful when 25 * doing multiple accesses to the same area (the programmer has to do the 26 * checks by hand with "access_ok()") 27 */ 28 #define __put_user(x, ptr) \ 29 __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) 30 #define __get_user(x, ptr) \ 31 __get_user_nocheck((x), (ptr), sizeof(*(ptr))) 32 33 /* 34 * The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to 35 * encode the bits we need for resolving the exception. See the 36 * more extensive comments with fixup_inline_exception below for 37 * more information. 38 */ 39 #define EXC(label,cont,res,err) \ 40 ".section __ex_table,\"a\"\n" \ 41 " .long "#label"-.\n" \ 42 " lda "#res","#cont"-"#label"("#err")\n" \ 43 ".previous\n" 44 45 extern void __get_user_unknown(void); 46 47 #define __get_user_nocheck(x, ptr, size) \ 48 ({ \ 49 long __gu_err = 0; \ 50 unsigned long __gu_val; \ 51 __chk_user_ptr(ptr); \ 52 switch (size) { \ 53 case 1: __get_user_8(ptr); break; \ 54 case 2: __get_user_16(ptr); break; \ 55 case 4: __get_user_32(ptr); break; \ 56 case 8: __get_user_64(ptr); break; \ 57 default: __get_user_unknown(); break; \ 58 } \ 59 (x) = (__force __typeof__(*(ptr))) __gu_val; \ 60 __gu_err; \ 61 }) 62 63 #define __get_user_check(x, ptr, size) \ 64 ({ \ 65 long __gu_err = -EFAULT; \ 66 unsigned long __gu_val = 0; \ 67 const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ 68 if (__access_ok(__gu_addr, size)) { \ 69 __gu_err = 0; \ 70 switch (size) { \ 71 case 1: __get_user_8(__gu_addr); break; \ 72 case 2: __get_user_16(__gu_addr); break; \ 73 case 4: __get_user_32(__gu_addr); break; \ 74 case 8: __get_user_64(__gu_addr); break; \ 75 default: __get_user_unknown(); break; \ 76 } \ 77 } \ 78 (x) = (__force __typeof__(*(ptr))) __gu_val; \ 79 __gu_err; \ 80 }) 81 82 struct __large_struct { unsigned long buf[100]; }; 83 #define __m(x) (*(struct __large_struct __user *)(x)) 84 85 #define __get_user_64(addr) \ 86 __asm__("1: ldq %0,%2\n" \ 87 "2:\n" \ 88 EXC(1b,2b,%0,%1) \ 89 : "=r"(__gu_val), "=r"(__gu_err) \ 90 : "m"(__m(addr)), "1"(__gu_err)) 91 92 #define __get_user_32(addr) \ 93 __asm__("1: ldl %0,%2\n" \ 94 "2:\n" \ 95 EXC(1b,2b,%0,%1) \ 96 : "=r"(__gu_val), "=r"(__gu_err) \ 97 : "m"(__m(addr)), "1"(__gu_err)) 98 99 #ifdef __alpha_bwx__ 100 /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */ 101 102 #define __get_user_16(addr) \ 103 __asm__("1: ldwu %0,%2\n" \ 104 "2:\n" \ 105 EXC(1b,2b,%0,%1) \ 106 : "=r"(__gu_val), "=r"(__gu_err) \ 107 : "m"(__m(addr)), "1"(__gu_err)) 108 109 #define __get_user_8(addr) \ 110 __asm__("1: ldbu %0,%2\n" \ 111 "2:\n" \ 112 EXC(1b,2b,%0,%1) \ 113 : "=r"(__gu_val), "=r"(__gu_err) \ 114 : "m"(__m(addr)), "1"(__gu_err)) 115 #else 116 /* Unfortunately, we can't get an unaligned access trap for the sub-word 117 load, so we have to do a general unaligned operation. */ 118 119 #define __get_user_16(addr) \ 120 { \ 121 long __gu_tmp; \ 122 __asm__("1: ldq_u %0,0(%3)\n" \ 123 "2: ldq_u %1,1(%3)\n" \ 124 " extwl %0,%3,%0\n" \ 125 " extwh %1,%3,%1\n" \ 126 " or %0,%1,%0\n" \ 127 "3:\n" \ 128 EXC(1b,3b,%0,%2) \ 129 EXC(2b,3b,%0,%2) \ 130 : "=&r"(__gu_val), "=&r"(__gu_tmp), "=r"(__gu_err) \ 131 : "r"(addr), "2"(__gu_err)); \ 132 } 133 134 #define __get_user_8(addr) \ 135 __asm__("1: ldq_u %0,0(%2)\n" \ 136 " extbl %0,%2,%0\n" \ 137 "2:\n" \ 138 EXC(1b,2b,%0,%1) \ 139 : "=&r"(__gu_val), "=r"(__gu_err) \ 140 : "r"(addr), "1"(__gu_err)) 141 #endif 142 143 extern void __put_user_unknown(void); 144 145 #define __put_user_nocheck(x, ptr, size) \ 146 ({ \ 147 long __pu_err = 0; \ 148 __chk_user_ptr(ptr); \ 149 switch (size) { \ 150 case 1: __put_user_8(x, ptr); break; \ 151 case 2: __put_user_16(x, ptr); break; \ 152 case 4: __put_user_32(x, ptr); break; \ 153 case 8: __put_user_64(x, ptr); break; \ 154 default: __put_user_unknown(); break; \ 155 } \ 156 __pu_err; \ 157 }) 158 159 #define __put_user_check(x, ptr, size) \ 160 ({ \ 161 long __pu_err = -EFAULT; \ 162 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ 163 if (__access_ok(__pu_addr, size)) { \ 164 __pu_err = 0; \ 165 switch (size) { \ 166 case 1: __put_user_8(x, __pu_addr); break; \ 167 case 2: __put_user_16(x, __pu_addr); break; \ 168 case 4: __put_user_32(x, __pu_addr); break; \ 169 case 8: __put_user_64(x, __pu_addr); break; \ 170 default: __put_user_unknown(); break; \ 171 } \ 172 } \ 173 __pu_err; \ 174 }) 175 176 /* 177 * The "__put_user_xx()" macros tell gcc they read from memory 178 * instead of writing: this is because they do not write to 179 * any memory gcc knows about, so there are no aliasing issues 180 */ 181 #define __put_user_64(x, addr) \ 182 __asm__ __volatile__("1: stq %r2,%1\n" \ 183 "2:\n" \ 184 EXC(1b,2b,$31,%0) \ 185 : "=r"(__pu_err) \ 186 : "m" (__m(addr)), "rJ" (x), "0"(__pu_err)) 187 188 #define __put_user_32(x, addr) \ 189 __asm__ __volatile__("1: stl %r2,%1\n" \ 190 "2:\n" \ 191 EXC(1b,2b,$31,%0) \ 192 : "=r"(__pu_err) \ 193 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 194 195 #ifdef __alpha_bwx__ 196 /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */ 197 198 #define __put_user_16(x, addr) \ 199 __asm__ __volatile__("1: stw %r2,%1\n" \ 200 "2:\n" \ 201 EXC(1b,2b,$31,%0) \ 202 : "=r"(__pu_err) \ 203 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 204 205 #define __put_user_8(x, addr) \ 206 __asm__ __volatile__("1: stb %r2,%1\n" \ 207 "2:\n" \ 208 EXC(1b,2b,$31,%0) \ 209 : "=r"(__pu_err) \ 210 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 211 #else 212 /* Unfortunately, we can't get an unaligned access trap for the sub-word 213 write, so we have to do a general unaligned operation. */ 214 215 #define __put_user_16(x, addr) \ 216 { \ 217 long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4; \ 218 __asm__ __volatile__( \ 219 "1: ldq_u %2,1(%5)\n" \ 220 "2: ldq_u %1,0(%5)\n" \ 221 " inswh %6,%5,%4\n" \ 222 " inswl %6,%5,%3\n" \ 223 " mskwh %2,%5,%2\n" \ 224 " mskwl %1,%5,%1\n" \ 225 " or %2,%4,%2\n" \ 226 " or %1,%3,%1\n" \ 227 "3: stq_u %2,1(%5)\n" \ 228 "4: stq_u %1,0(%5)\n" \ 229 "5:\n" \ 230 EXC(1b,5b,$31,%0) \ 231 EXC(2b,5b,$31,%0) \ 232 EXC(3b,5b,$31,%0) \ 233 EXC(4b,5b,$31,%0) \ 234 : "=r"(__pu_err), "=&r"(__pu_tmp1), \ 235 "=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \ 236 "=&r"(__pu_tmp4) \ 237 : "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \ 238 } 239 240 #define __put_user_8(x, addr) \ 241 { \ 242 long __pu_tmp1, __pu_tmp2; \ 243 __asm__ __volatile__( \ 244 "1: ldq_u %1,0(%4)\n" \ 245 " insbl %3,%4,%2\n" \ 246 " mskbl %1,%4,%1\n" \ 247 " or %1,%2,%1\n" \ 248 "2: stq_u %1,0(%4)\n" \ 249 "3:\n" \ 250 EXC(1b,3b,$31,%0) \ 251 EXC(2b,3b,$31,%0) \ 252 : "=r"(__pu_err), \ 253 "=&r"(__pu_tmp1), "=&r"(__pu_tmp2) \ 254 : "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \ 255 } 256 #endif 257 258 259 /* 260 * Complex access routines 261 */ 262 263 extern long __copy_user(void *to, const void *from, long len); 264 265 static inline unsigned long 266 raw_copy_from_user(void *to, const void __user *from, unsigned long len) 267 { 268 return __copy_user(to, (__force const void *)from, len); 269 } 270 271 static inline unsigned long 272 raw_copy_to_user(void __user *to, const void *from, unsigned long len) 273 { 274 return __copy_user((__force void *)to, from, len); 275 } 276 277 extern long __clear_user(void __user *to, long len); 278 279 static inline long 280 clear_user(void __user *to, long len) 281 { 282 if (__access_ok(to, len)) 283 len = __clear_user(to, len); 284 return len; 285 } 286 287 extern long strncpy_from_user(char *dest, const char __user *src, long count); 288 extern __must_check long strnlen_user(const char __user *str, long n); 289 290 #include <asm/extable.h> 291 292 #endif /* __ALPHA_UACCESS_H */ 293