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 #define __get_user_16(addr) \ 100 __asm__("1: ldwu %0,%2\n" \ 101 "2:\n" \ 102 EXC(1b,2b,%0,%1) \ 103 : "=r"(__gu_val), "=r"(__gu_err) \ 104 : "m"(__m(addr)), "1"(__gu_err)) 105 106 #define __get_user_8(addr) \ 107 __asm__("1: ldbu %0,%2\n" \ 108 "2:\n" \ 109 EXC(1b,2b,%0,%1) \ 110 : "=r"(__gu_val), "=r"(__gu_err) \ 111 : "m"(__m(addr)), "1"(__gu_err)) 112 113 extern void __put_user_unknown(void); 114 115 #define __put_user_nocheck(x, ptr, size) \ 116 ({ \ 117 long __pu_err = 0; \ 118 __chk_user_ptr(ptr); \ 119 switch (size) { \ 120 case 1: __put_user_8(x, ptr); break; \ 121 case 2: __put_user_16(x, ptr); break; \ 122 case 4: __put_user_32(x, ptr); break; \ 123 case 8: __put_user_64(x, ptr); break; \ 124 default: __put_user_unknown(); break; \ 125 } \ 126 __pu_err; \ 127 }) 128 129 #define __put_user_check(x, ptr, size) \ 130 ({ \ 131 long __pu_err = -EFAULT; \ 132 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ 133 if (__access_ok(__pu_addr, size)) { \ 134 __pu_err = 0; \ 135 switch (size) { \ 136 case 1: __put_user_8(x, __pu_addr); break; \ 137 case 2: __put_user_16(x, __pu_addr); break; \ 138 case 4: __put_user_32(x, __pu_addr); break; \ 139 case 8: __put_user_64(x, __pu_addr); break; \ 140 default: __put_user_unknown(); break; \ 141 } \ 142 } \ 143 __pu_err; \ 144 }) 145 146 /* 147 * The "__put_user_xx()" macros tell gcc they read from memory 148 * instead of writing: this is because they do not write to 149 * any memory gcc knows about, so there are no aliasing issues 150 */ 151 #define __put_user_64(x, addr) \ 152 __asm__ __volatile__("1: stq %r2,%1\n" \ 153 "2:\n" \ 154 EXC(1b,2b,$31,%0) \ 155 : "=r"(__pu_err) \ 156 : "m" (__m(addr)), "rJ" (x), "0"(__pu_err)) 157 158 #define __put_user_32(x, addr) \ 159 __asm__ __volatile__("1: stl %r2,%1\n" \ 160 "2:\n" \ 161 EXC(1b,2b,$31,%0) \ 162 : "=r"(__pu_err) \ 163 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 164 165 #define __put_user_16(x, addr) \ 166 __asm__ __volatile__("1: stw %r2,%1\n" \ 167 "2:\n" \ 168 EXC(1b,2b,$31,%0) \ 169 : "=r"(__pu_err) \ 170 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 171 172 #define __put_user_8(x, addr) \ 173 __asm__ __volatile__("1: stb %r2,%1\n" \ 174 "2:\n" \ 175 EXC(1b,2b,$31,%0) \ 176 : "=r"(__pu_err) \ 177 : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) 178 179 /* 180 * Complex access routines 181 */ 182 183 extern long __copy_user(void *to, const void *from, long len); 184 185 static inline unsigned long 186 raw_copy_from_user(void *to, const void __user *from, unsigned long len) 187 { 188 return __copy_user(to, (__force const void *)from, len); 189 } 190 191 static inline unsigned long 192 raw_copy_to_user(void __user *to, const void *from, unsigned long len) 193 { 194 return __copy_user((__force void *)to, from, len); 195 } 196 197 extern long __clear_user(void __user *to, long len); 198 199 static inline long 200 clear_user(void __user *to, long len) 201 { 202 if (__access_ok(to, len)) 203 len = __clear_user(to, len); 204 return len; 205 } 206 207 extern long strncpy_from_user(char *dest, const char __user *src, long count); 208 extern __must_check long strnlen_user(const char __user *str, long n); 209 210 #include <asm/extable.h> 211 212 #endif /* __ALPHA_UACCESS_H */ 213