1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_ATOMIC64_32_H 3 #define _ASM_X86_ATOMIC64_32_H 4 5 #include <linux/compiler.h> 6 #include <linux/types.h> 7 //#include <asm/cmpxchg.h> 8 9 /* An 64bit atomic type */ 10 11 typedef struct { 12 s64 __aligned(8) counter; 13 } atomic64_t; 14 15 #define ATOMIC64_INIT(val) { (val) } 16 17 #define __ATOMIC64_DECL(sym) void atomic64_##sym(atomic64_t *, ...) 18 #ifndef ATOMIC64_EXPORT 19 #define ATOMIC64_DECL_ONE __ATOMIC64_DECL 20 #else 21 #define ATOMIC64_DECL_ONE(sym) __ATOMIC64_DECL(sym); \ 22 ATOMIC64_EXPORT(atomic64_##sym) 23 #endif 24 25 #ifdef CONFIG_X86_CMPXCHG64 26 #define __alternative_atomic64(f, g, out, in...) \ 27 asm volatile("call %P[func]" \ 28 : out : [func] "i" (atomic64_##g##_cx8), ## in) 29 30 #define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8) 31 #else 32 #define __alternative_atomic64(f, g, out, in...) \ 33 alternative_call(atomic64_##f##_386, atomic64_##g##_cx8, \ 34 X86_FEATURE_CX8, ASM_OUTPUT2(out), ## in) 35 36 #define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8); \ 37 ATOMIC64_DECL_ONE(sym##_386) 38 39 ATOMIC64_DECL_ONE(add_386); 40 ATOMIC64_DECL_ONE(sub_386); 41 ATOMIC64_DECL_ONE(inc_386); 42 ATOMIC64_DECL_ONE(dec_386); 43 #endif 44 45 #define alternative_atomic64(f, out, in...) \ 46 __alternative_atomic64(f, f, ASM_OUTPUT2(out), ## in) 47 48 ATOMIC64_DECL(read); 49 ATOMIC64_DECL(set); 50 ATOMIC64_DECL(xchg); 51 ATOMIC64_DECL(add_return); 52 ATOMIC64_DECL(sub_return); 53 ATOMIC64_DECL(inc_return); 54 ATOMIC64_DECL(dec_return); 55 ATOMIC64_DECL(dec_if_positive); 56 ATOMIC64_DECL(inc_not_zero); 57 ATOMIC64_DECL(add_unless); 58 59 #undef ATOMIC64_DECL 60 #undef ATOMIC64_DECL_ONE 61 #undef __ATOMIC64_DECL 62 #undef ATOMIC64_EXPORT 63 64 /** 65 * arch_atomic64_cmpxchg - cmpxchg atomic64 variable 66 * @v: pointer to type atomic64_t 67 * @o: expected value 68 * @n: new value 69 * 70 * Atomically sets @v to @n if it was equal to @o and returns 71 * the old value. 72 */ 73 74 static inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 o, s64 n) 75 { 76 return arch_cmpxchg64(&v->counter, o, n); 77 } 78 79 /** 80 * arch_atomic64_xchg - xchg atomic64 variable 81 * @v: pointer to type atomic64_t 82 * @n: value to assign 83 * 84 * Atomically xchgs the value of @v to @n and returns 85 * the old value. 86 */ 87 static inline s64 arch_atomic64_xchg(atomic64_t *v, s64 n) 88 { 89 s64 o; 90 unsigned high = (unsigned)(n >> 32); 91 unsigned low = (unsigned)n; 92 alternative_atomic64(xchg, "=&A" (o), 93 "S" (v), "b" (low), "c" (high) 94 : "memory"); 95 return o; 96 } 97 98 /** 99 * arch_atomic64_set - set atomic64 variable 100 * @v: pointer to type atomic64_t 101 * @i: value to assign 102 * 103 * Atomically sets the value of @v to @n. 104 */ 105 static inline void arch_atomic64_set(atomic64_t *v, s64 i) 106 { 107 unsigned high = (unsigned)(i >> 32); 108 unsigned low = (unsigned)i; 109 alternative_atomic64(set, /* no output */, 110 "S" (v), "b" (low), "c" (high) 111 : "eax", "edx", "memory"); 112 } 113 114 /** 115 * arch_atomic64_read - read atomic64 variable 116 * @v: pointer to type atomic64_t 117 * 118 * Atomically reads the value of @v and returns it. 119 */ 120 static inline s64 arch_atomic64_read(const atomic64_t *v) 121 { 122 s64 r; 123 alternative_atomic64(read, "=&A" (r), "c" (v) : "memory"); 124 return r; 125 } 126 127 /** 128 * arch_atomic64_add_return - add and return 129 * @i: integer value to add 130 * @v: pointer to type atomic64_t 131 * 132 * Atomically adds @i to @v and returns @i + *@v 133 */ 134 static inline s64 arch_atomic64_add_return(s64 i, atomic64_t *v) 135 { 136 alternative_atomic64(add_return, 137 ASM_OUTPUT2("+A" (i), "+c" (v)), 138 ASM_NO_INPUT_CLOBBER("memory")); 139 return i; 140 } 141 142 /* 143 * Other variants with different arithmetic operators: 144 */ 145 static inline s64 arch_atomic64_sub_return(s64 i, atomic64_t *v) 146 { 147 alternative_atomic64(sub_return, 148 ASM_OUTPUT2("+A" (i), "+c" (v)), 149 ASM_NO_INPUT_CLOBBER("memory")); 150 return i; 151 } 152 153 static inline s64 arch_atomic64_inc_return(atomic64_t *v) 154 { 155 s64 a; 156 alternative_atomic64(inc_return, "=&A" (a), 157 "S" (v) : "memory", "ecx"); 158 return a; 159 } 160 #define arch_atomic64_inc_return arch_atomic64_inc_return 161 162 static inline s64 arch_atomic64_dec_return(atomic64_t *v) 163 { 164 s64 a; 165 alternative_atomic64(dec_return, "=&A" (a), 166 "S" (v) : "memory", "ecx"); 167 return a; 168 } 169 #define arch_atomic64_dec_return arch_atomic64_dec_return 170 171 /** 172 * arch_atomic64_add - add integer to atomic64 variable 173 * @i: integer value to add 174 * @v: pointer to type atomic64_t 175 * 176 * Atomically adds @i to @v. 177 */ 178 static inline s64 arch_atomic64_add(s64 i, atomic64_t *v) 179 { 180 __alternative_atomic64(add, add_return, 181 ASM_OUTPUT2("+A" (i), "+c" (v)), 182 ASM_NO_INPUT_CLOBBER("memory")); 183 return i; 184 } 185 186 /** 187 * arch_atomic64_sub - subtract the atomic64 variable 188 * @i: integer value to subtract 189 * @v: pointer to type atomic64_t 190 * 191 * Atomically subtracts @i from @v. 192 */ 193 static inline s64 arch_atomic64_sub(s64 i, atomic64_t *v) 194 { 195 __alternative_atomic64(sub, sub_return, 196 ASM_OUTPUT2("+A" (i), "+c" (v)), 197 ASM_NO_INPUT_CLOBBER("memory")); 198 return i; 199 } 200 201 /** 202 * arch_atomic64_inc - increment atomic64 variable 203 * @v: pointer to type atomic64_t 204 * 205 * Atomically increments @v by 1. 206 */ 207 static inline void arch_atomic64_inc(atomic64_t *v) 208 { 209 __alternative_atomic64(inc, inc_return, /* no output */, 210 "S" (v) : "memory", "eax", "ecx", "edx"); 211 } 212 #define arch_atomic64_inc arch_atomic64_inc 213 214 /** 215 * arch_atomic64_dec - decrement atomic64 variable 216 * @v: pointer to type atomic64_t 217 * 218 * Atomically decrements @v by 1. 219 */ 220 static inline void arch_atomic64_dec(atomic64_t *v) 221 { 222 __alternative_atomic64(dec, dec_return, /* no output */, 223 "S" (v) : "memory", "eax", "ecx", "edx"); 224 } 225 #define arch_atomic64_dec arch_atomic64_dec 226 227 /** 228 * arch_atomic64_add_unless - add unless the number is a given value 229 * @v: pointer of type atomic64_t 230 * @a: the amount to add to v... 231 * @u: ...unless v is equal to u. 232 * 233 * Atomically adds @a to @v, so long as it was not @u. 234 * Returns non-zero if the add was done, zero otherwise. 235 */ 236 static inline int arch_atomic64_add_unless(atomic64_t *v, s64 a, s64 u) 237 { 238 unsigned low = (unsigned)u; 239 unsigned high = (unsigned)(u >> 32); 240 alternative_atomic64(add_unless, 241 ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)), 242 "S" (v) : "memory"); 243 return (int)a; 244 } 245 246 static inline int arch_atomic64_inc_not_zero(atomic64_t *v) 247 { 248 int r; 249 alternative_atomic64(inc_not_zero, "=&a" (r), 250 "S" (v) : "ecx", "edx", "memory"); 251 return r; 252 } 253 #define arch_atomic64_inc_not_zero arch_atomic64_inc_not_zero 254 255 static inline s64 arch_atomic64_dec_if_positive(atomic64_t *v) 256 { 257 s64 r; 258 alternative_atomic64(dec_if_positive, "=&A" (r), 259 "S" (v) : "ecx", "memory"); 260 return r; 261 } 262 #define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive 263 264 #undef alternative_atomic64 265 #undef __alternative_atomic64 266 267 static inline void arch_atomic64_and(s64 i, atomic64_t *v) 268 { 269 s64 old, c = 0; 270 271 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 272 c = old; 273 } 274 275 static inline s64 arch_atomic64_fetch_and(s64 i, atomic64_t *v) 276 { 277 s64 old, c = 0; 278 279 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 280 c = old; 281 282 return old; 283 } 284 285 static inline void arch_atomic64_or(s64 i, atomic64_t *v) 286 { 287 s64 old, c = 0; 288 289 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 290 c = old; 291 } 292 293 static inline s64 arch_atomic64_fetch_or(s64 i, atomic64_t *v) 294 { 295 s64 old, c = 0; 296 297 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 298 c = old; 299 300 return old; 301 } 302 303 static inline void arch_atomic64_xor(s64 i, atomic64_t *v) 304 { 305 s64 old, c = 0; 306 307 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 308 c = old; 309 } 310 311 static inline s64 arch_atomic64_fetch_xor(s64 i, atomic64_t *v) 312 { 313 s64 old, c = 0; 314 315 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 316 c = old; 317 318 return old; 319 } 320 321 static inline s64 arch_atomic64_fetch_add(s64 i, atomic64_t *v) 322 { 323 s64 old, c = 0; 324 325 while ((old = arch_atomic64_cmpxchg(v, c, c + i)) != c) 326 c = old; 327 328 return old; 329 } 330 331 #define arch_atomic64_fetch_sub(i, v) arch_atomic64_fetch_add(-(i), (v)) 332 333 #endif /* _ASM_X86_ATOMIC64_32_H */ 334