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 __always_inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 o, s64 n) 75 { 76 return arch_cmpxchg64(&v->counter, o, n); 77 } 78 #define arch_atomic64_cmpxchg arch_atomic64_cmpxchg 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 __always_inline s64 arch_atomic64_xchg(atomic64_t *v, s64 n) 89 { 90 s64 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 #define arch_atomic64_xchg arch_atomic64_xchg 99 100 /** 101 * arch_atomic64_set - set atomic64 variable 102 * @v: pointer to type atomic64_t 103 * @i: value to assign 104 * 105 * Atomically sets the value of @v to @n. 106 */ 107 static __always_inline void arch_atomic64_set(atomic64_t *v, s64 i) 108 { 109 unsigned high = (unsigned)(i >> 32); 110 unsigned low = (unsigned)i; 111 alternative_atomic64(set, /* no output */, 112 "S" (v), "b" (low), "c" (high) 113 : "eax", "edx", "memory"); 114 } 115 116 /** 117 * arch_atomic64_read - read atomic64 variable 118 * @v: pointer to type atomic64_t 119 * 120 * Atomically reads the value of @v and returns it. 121 */ 122 static __always_inline s64 arch_atomic64_read(const atomic64_t *v) 123 { 124 s64 r; 125 alternative_atomic64(read, "=&A" (r), "c" (v) : "memory"); 126 return r; 127 } 128 129 /** 130 * arch_atomic64_add_return - add and return 131 * @i: integer value to add 132 * @v: pointer to type atomic64_t 133 * 134 * Atomically adds @i to @v and returns @i + *@v 135 */ 136 static __always_inline s64 arch_atomic64_add_return(s64 i, atomic64_t *v) 137 { 138 alternative_atomic64(add_return, 139 ASM_OUTPUT2("+A" (i), "+c" (v)), 140 ASM_NO_INPUT_CLOBBER("memory")); 141 return i; 142 } 143 #define arch_atomic64_add_return arch_atomic64_add_return 144 145 /* 146 * Other variants with different arithmetic operators: 147 */ 148 static __always_inline s64 arch_atomic64_sub_return(s64 i, atomic64_t *v) 149 { 150 alternative_atomic64(sub_return, 151 ASM_OUTPUT2("+A" (i), "+c" (v)), 152 ASM_NO_INPUT_CLOBBER("memory")); 153 return i; 154 } 155 #define arch_atomic64_sub_return arch_atomic64_sub_return 156 157 static __always_inline s64 arch_atomic64_inc_return(atomic64_t *v) 158 { 159 s64 a; 160 alternative_atomic64(inc_return, "=&A" (a), 161 "S" (v) : "memory", "ecx"); 162 return a; 163 } 164 #define arch_atomic64_inc_return arch_atomic64_inc_return 165 166 static __always_inline s64 arch_atomic64_dec_return(atomic64_t *v) 167 { 168 s64 a; 169 alternative_atomic64(dec_return, "=&A" (a), 170 "S" (v) : "memory", "ecx"); 171 return a; 172 } 173 #define arch_atomic64_dec_return arch_atomic64_dec_return 174 175 /** 176 * arch_atomic64_add - add integer to atomic64 variable 177 * @i: integer value to add 178 * @v: pointer to type atomic64_t 179 * 180 * Atomically adds @i to @v. 181 */ 182 static __always_inline s64 arch_atomic64_add(s64 i, atomic64_t *v) 183 { 184 __alternative_atomic64(add, add_return, 185 ASM_OUTPUT2("+A" (i), "+c" (v)), 186 ASM_NO_INPUT_CLOBBER("memory")); 187 return i; 188 } 189 190 /** 191 * arch_atomic64_sub - subtract the atomic64 variable 192 * @i: integer value to subtract 193 * @v: pointer to type atomic64_t 194 * 195 * Atomically subtracts @i from @v. 196 */ 197 static __always_inline s64 arch_atomic64_sub(s64 i, atomic64_t *v) 198 { 199 __alternative_atomic64(sub, sub_return, 200 ASM_OUTPUT2("+A" (i), "+c" (v)), 201 ASM_NO_INPUT_CLOBBER("memory")); 202 return i; 203 } 204 205 /** 206 * arch_atomic64_inc - increment atomic64 variable 207 * @v: pointer to type atomic64_t 208 * 209 * Atomically increments @v by 1. 210 */ 211 static __always_inline void arch_atomic64_inc(atomic64_t *v) 212 { 213 __alternative_atomic64(inc, inc_return, /* no output */, 214 "S" (v) : "memory", "eax", "ecx", "edx"); 215 } 216 #define arch_atomic64_inc arch_atomic64_inc 217 218 /** 219 * arch_atomic64_dec - decrement atomic64 variable 220 * @v: pointer to type atomic64_t 221 * 222 * Atomically decrements @v by 1. 223 */ 224 static __always_inline void arch_atomic64_dec(atomic64_t *v) 225 { 226 __alternative_atomic64(dec, dec_return, /* no output */, 227 "S" (v) : "memory", "eax", "ecx", "edx"); 228 } 229 #define arch_atomic64_dec arch_atomic64_dec 230 231 /** 232 * arch_atomic64_add_unless - add unless the number is a given value 233 * @v: pointer of type atomic64_t 234 * @a: the amount to add to v... 235 * @u: ...unless v is equal to u. 236 * 237 * Atomically adds @a to @v, so long as it was not @u. 238 * Returns non-zero if the add was done, zero otherwise. 239 */ 240 static __always_inline int arch_atomic64_add_unless(atomic64_t *v, s64 a, s64 u) 241 { 242 unsigned low = (unsigned)u; 243 unsigned high = (unsigned)(u >> 32); 244 alternative_atomic64(add_unless, 245 ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)), 246 "S" (v) : "memory"); 247 return (int)a; 248 } 249 #define arch_atomic64_add_unless arch_atomic64_add_unless 250 251 static __always_inline int arch_atomic64_inc_not_zero(atomic64_t *v) 252 { 253 int r; 254 alternative_atomic64(inc_not_zero, "=&a" (r), 255 "S" (v) : "ecx", "edx", "memory"); 256 return r; 257 } 258 #define arch_atomic64_inc_not_zero arch_atomic64_inc_not_zero 259 260 static __always_inline s64 arch_atomic64_dec_if_positive(atomic64_t *v) 261 { 262 s64 r; 263 alternative_atomic64(dec_if_positive, "=&A" (r), 264 "S" (v) : "ecx", "memory"); 265 return r; 266 } 267 #define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive 268 269 #undef alternative_atomic64 270 #undef __alternative_atomic64 271 272 static __always_inline void arch_atomic64_and(s64 i, atomic64_t *v) 273 { 274 s64 old, c = 0; 275 276 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 277 c = old; 278 } 279 280 static __always_inline s64 arch_atomic64_fetch_and(s64 i, atomic64_t *v) 281 { 282 s64 old, c = 0; 283 284 while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c) 285 c = old; 286 287 return old; 288 } 289 #define arch_atomic64_fetch_and arch_atomic64_fetch_and 290 291 static __always_inline void arch_atomic64_or(s64 i, atomic64_t *v) 292 { 293 s64 old, c = 0; 294 295 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 296 c = old; 297 } 298 299 static __always_inline s64 arch_atomic64_fetch_or(s64 i, atomic64_t *v) 300 { 301 s64 old, c = 0; 302 303 while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c) 304 c = old; 305 306 return old; 307 } 308 #define arch_atomic64_fetch_or arch_atomic64_fetch_or 309 310 static __always_inline void arch_atomic64_xor(s64 i, atomic64_t *v) 311 { 312 s64 old, c = 0; 313 314 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 315 c = old; 316 } 317 318 static __always_inline s64 arch_atomic64_fetch_xor(s64 i, atomic64_t *v) 319 { 320 s64 old, c = 0; 321 322 while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c) 323 c = old; 324 325 return old; 326 } 327 #define arch_atomic64_fetch_xor arch_atomic64_fetch_xor 328 329 static __always_inline s64 arch_atomic64_fetch_add(s64 i, atomic64_t *v) 330 { 331 s64 old, c = 0; 332 333 while ((old = arch_atomic64_cmpxchg(v, c, c + i)) != c) 334 c = old; 335 336 return old; 337 } 338 #define arch_atomic64_fetch_add arch_atomic64_fetch_add 339 340 #define arch_atomic64_fetch_sub(i, v) arch_atomic64_fetch_add(-(i), (v)) 341 342 #endif /* _ASM_X86_ATOMIC64_32_H */ 343