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 u64 __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 long long arch_atomic64_cmpxchg(atomic64_t *v, long long o, 75 long long n) 76 { 77 return arch_cmpxchg64(&v->counter, o, n); 78 } 79 80 /** 81 * arch_atomic64_xchg - xchg atomic64 variable 82 * @v: pointer to type atomic64_t 83 * @n: value to assign 84 * 85 * Atomically xchgs the value of @v to @n and returns 86 * the old value. 87 */ 88 static inline long long arch_atomic64_xchg(atomic64_t *v, long long n) 89 { 90 long long o; 91 unsigned high = (unsigned)(n >> 32); 92 unsigned low = (unsigned)n; 93 alternative_atomic64(xchg, "=&A" (o), 94 "S" (v), "b" (low), "c" (high) 95 : "memory"); 96 return o; 97 } 98 99 /** 100 * arch_atomic64_set - set atomic64 variable 101 * @v: pointer to type atomic64_t 102 * @i: value to assign 103 * 104 * Atomically sets the value of @v to @n. 105 */ 106 static inline void arch_atomic64_set(atomic64_t *v, long long i) 107 { 108 unsigned high = (unsigned)(i >> 32); 109 unsigned low = (unsigned)i; 110 alternative_atomic64(set, /* no output */, 111 "S" (v), "b" (low), "c" (high) 112 : "eax", "edx", "memory"); 113 } 114 115 /** 116 * arch_atomic64_read - read atomic64 variable 117 * @v: pointer to type atomic64_t 118 * 119 * Atomically reads the value of @v and returns it. 120 */ 121 static inline long long arch_atomic64_read(const atomic64_t *v) 122 { 123 long long r; 124 alternative_atomic64(read, "=&A" (r), "c" (v) : "memory"); 125 return r; 126 } 127 128 /** 129 * arch_atomic64_add_return - add and return 130 * @i: integer value to add 131 * @v: pointer to type atomic64_t 132 * 133 * Atomically adds @i to @v and returns @i + *@v 134 */ 135 static inline long long arch_atomic64_add_return(long long i, atomic64_t *v) 136 { 137 alternative_atomic64(add_return, 138 ASM_OUTPUT2("+A" (i), "+c" (v)), 139 ASM_NO_INPUT_CLOBBER("memory")); 140 return i; 141 } 142 143 /* 144 * Other variants with different arithmetic operators: 145 */ 146 static inline long long arch_atomic64_sub_return(long long i, atomic64_t *v) 147 { 148 alternative_atomic64(sub_return, 149 ASM_OUTPUT2("+A" (i), "+c" (v)), 150 ASM_NO_INPUT_CLOBBER("memory")); 151 return i; 152 } 153 154 static inline long long arch_atomic64_inc_return(atomic64_t *v) 155 { 156 long long a; 157 alternative_atomic64(inc_return, "=&A" (a), 158 "S" (v) : "memory", "ecx"); 159 return a; 160 } 161 #define arch_atomic64_inc_return arch_atomic64_inc_return 162 163 static inline long long arch_atomic64_dec_return(atomic64_t *v) 164 { 165 long long a; 166 alternative_atomic64(dec_return, "=&A" (a), 167 "S" (v) : "memory", "ecx"); 168 return a; 169 } 170 #define arch_atomic64_dec_return arch_atomic64_dec_return 171 172 /** 173 * arch_atomic64_add - add integer to atomic64 variable 174 * @i: integer value to add 175 * @v: pointer to type atomic64_t 176 * 177 * Atomically adds @i to @v. 178 */ 179 static inline long long arch_atomic64_add(long long i, atomic64_t *v) 180 { 181 __alternative_atomic64(add, add_return, 182 ASM_OUTPUT2("+A" (i), "+c" (v)), 183 ASM_NO_INPUT_CLOBBER("memory")); 184 return i; 185 } 186 187 /** 188 * arch_atomic64_sub - subtract the atomic64 variable 189 * @i: integer value to subtract 190 * @v: pointer to type atomic64_t 191 * 192 * Atomically subtracts @i from @v. 193 */ 194 static inline long long arch_atomic64_sub(long long i, atomic64_t *v) 195 { 196 __alternative_atomic64(sub, sub_return, 197 ASM_OUTPUT2("+A" (i), "+c" (v)), 198 ASM_NO_INPUT_CLOBBER("memory")); 199 return i; 200 } 201 202 /** 203 * arch_atomic64_inc - increment atomic64 variable 204 * @v: pointer to type atomic64_t 205 * 206 * Atomically increments @v by 1. 207 */ 208 static inline void arch_atomic64_inc(atomic64_t *v) 209 { 210 __alternative_atomic64(inc, inc_return, /* no output */, 211 "S" (v) : "memory", "eax", "ecx", "edx"); 212 } 213 #define arch_atomic64_inc arch_atomic64_inc 214 215 /** 216 * arch_atomic64_dec - decrement atomic64 variable 217 * @v: pointer to type atomic64_t 218 * 219 * Atomically decrements @v by 1. 220 */ 221 static inline void arch_atomic64_dec(atomic64_t *v) 222 { 223 __alternative_atomic64(dec, dec_return, /* no output */, 224 "S" (v) : "memory", "eax", "ecx", "edx"); 225 } 226 #define arch_atomic64_dec arch_atomic64_dec 227 228 /** 229 * arch_atomic64_add_unless - add unless the number is a given value 230 * @v: pointer of type atomic64_t 231 * @a: the amount to add to v... 232 * @u: ...unless v is equal to u. 233 * 234 * Atomically adds @a to @v, so long as it was not @u. 235 * Returns non-zero if the add was done, zero otherwise. 236 */ 237 static inline int arch_atomic64_add_unless(atomic64_t *v, long long a, 238 long long u) 239 { 240 unsigned low = (unsigned)u; 241 unsigned high = (unsigned)(u >> 32); 242 alternative_atomic64(add_unless, 243 ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)), 244 "S" (v) : "memory"); 245 return (int)a; 246 } 247 248 static inline int arch_atomic64_inc_not_zero(atomic64_t *v) 249 { 250 int r; 251 alternative_atomic64(inc_not_zero, "=&a" (r), 252 "S" (v) : "ecx", "edx", "memory"); 253 return r; 254 } 255 #define arch_atomic64_inc_not_zero arch_atomic64_inc_not_zero 256 257 static inline long long arch_atomic64_dec_if_positive(atomic64_t *v) 258 { 259 long long r; 260 alternative_atomic64(dec_if_positive, "=&A" (r), 261 "S" (v) : "ecx", "memory"); 262 return r; 263 } 264 #define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive 265 266 #undef alternative_atomic64 267 #undef __alternative_atomic64 268 269 static inline void arch_atomic64_and(long long i, atomic64_t *v) 270 { 271 long long old, c = 0; 272 273 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 274 c = old; 275 } 276 277 static inline long long arch_atomic64_fetch_and(long long i, atomic64_t *v) 278 { 279 long long old, c = 0; 280 281 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 282 c = old; 283 284 return old; 285 } 286 287 static inline void arch_atomic64_or(long long i, atomic64_t *v) 288 { 289 long long old, c = 0; 290 291 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 292 c = old; 293 } 294 295 static inline long long arch_atomic64_fetch_or(long long i, atomic64_t *v) 296 { 297 long long old, c = 0; 298 299 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 300 c = old; 301 302 return old; 303 } 304 305 static inline void arch_atomic64_xor(long long i, atomic64_t *v) 306 { 307 long long old, c = 0; 308 309 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 310 c = old; 311 } 312 313 static inline long long arch_atomic64_fetch_xor(long long i, atomic64_t *v) 314 { 315 long long old, c = 0; 316 317 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 318 c = old; 319 320 return old; 321 } 322 323 static inline long long arch_atomic64_fetch_add(long long i, atomic64_t *v) 324 { 325 long long old, c = 0; 326 327 while ((old = arch_atomic64_cmpxchg(v, c, c + i)) != c) 328 c = old; 329 330 return old; 331 } 332 333 #define arch_atomic64_fetch_sub(i, v) arch_atomic64_fetch_add(-(i), (v)) 334 335 #endif /* _ASM_X86_ATOMIC64_32_H */ 336