arch/mips/include/asm/futex.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (c) 2006  Ralf Baechle (ralf@linux-mips.org)
   7  */
   8 #ifndef _ASM_FUTEX_H
   9 #define _ASM_FUTEX_H
  10
  11 #ifdef __KERNEL__
  12
  13 #include <linux/futex.h>
  14 #include <linux/uaccess.h>
  15 #include <asm/asm-eva.h>
  16 #include <asm/barrier.h>
  17 #include <asm/compiler.h>
  18 #include <asm/errno.h>
  19 #include <asm/sync.h>
  20
  21 #define arch_futex_atomic_op_inuser arch_futex_atomic_op_inuser
  22 #define futex_atomic_cmpxchg_inatomic futex_atomic_cmpxchg_inatomic
  23 #include <asm-generic/futex.h>
  24
  25 #define __futex_atomic_op(op, insn, ret, oldval, uaddr, oparg)          \
  26 {                                                                       \
  27         if (cpu_has_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) {       \
  28                 __asm__ __volatile__(                                   \
  29                 "       .set    push                            \n"     \
  30                 "       .set    noat                            \n"     \
  31                 "       .set    push                            \n"     \
  32                 "       .set    arch=r4000                      \n"     \
  33                 "1:     ll      %1, %4  # __futex_atomic_op     \n"     \
  34                 "       .set    pop                             \n"     \
  35                 "       " insn  "                               \n"     \
  36                 "       .set    arch=r4000                      \n"     \
  37                 "2:     sc      $1, %2                          \n"     \
  38                 "       beqzl   $1, 1b                          \n"     \
  39                 __stringify(__WEAK_LLSC_MB) "                   \n"     \
  40                 "3:                                             \n"     \
  41                 "       .insn                                   \n"     \
  42                 "       .set    pop                             \n"     \
  43                 "       .section .fixup,\"ax\"                  \n"     \
  44                 "4:     li      %0, %6                          \n"     \
  45                 "       j       3b                              \n"     \
  46                 "       .previous                               \n"     \
  47                 "       .section __ex_table,\"a\"               \n"     \
  48                 "       "__UA_ADDR "\t1b, 4b                    \n"     \
  49                 "       "__UA_ADDR "\t2b, 4b                    \n"     \
  50                 "       .previous                               \n"     \
  51                 : "=r" (ret), "=&r" (oldval),                           \
  52                   "=" GCC_OFF_SMALL_ASM() (*uaddr)                              \
  53                 : "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg),  \
  54                   "i" (-EFAULT)                                         \
  55                 : "memory");                                            \
  56         } else if (cpu_has_llsc) {                                      \
  57                 __asm__ __volatile__(                                   \
  58                 "       .set    push                            \n"     \
  59                 "       .set    noat                            \n"     \
  60                 "       .set    push                            \n"     \
  61                 "       .set    "MIPS_ISA_ARCH_LEVEL"           \n"     \
  62                 "       " __SYNC(full, loongson3_war) "         \n"     \
  63                 "1:     "user_ll("%1", "%4")" # __futex_atomic_op\n"    \
  64                 "       .set    pop                             \n"     \
  65                 "       " insn  "                               \n"     \
  66                 "       .set    "MIPS_ISA_ARCH_LEVEL"           \n"     \
  67                 "2:     "user_sc("$1", "%2")"                   \n"     \
  68                 "       beqz    $1, 1b                          \n"     \
  69                 __stringify(__WEAK_LLSC_MB) "                   \n"     \
  70                 "3:                                             \n"     \
  71                 "       .insn                                   \n"     \
  72                 "       .set    pop                             \n"     \
  73                 "       .section .fixup,\"ax\"                  \n"     \
  74                 "4:     li      %0, %6                          \n"     \
  75                 "       j       3b                              \n"     \
  76                 "       .previous                               \n"     \
  77                 "       .section __ex_table,\"a\"               \n"     \
  78                 "       "__UA_ADDR "\t1b, 4b                    \n"     \
  79                 "       "__UA_ADDR "\t2b, 4b                    \n"     \
  80                 "       .previous                               \n"     \
  81                 : "=r" (ret), "=&r" (oldval),                           \
  82                   "=" GCC_OFF_SMALL_ASM() (*uaddr)                              \
  83                 : "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg),  \
  84                   "i" (-EFAULT)                                         \
  85                 : "memory");                                            \
  86         } else {                                                        \
  87                 /* fallback for non-SMP */                              \
  88                 ret = futex_atomic_op_inuser_local(op, oparg, oval, uaddr);     \
  89         }                                                               \
  90 }
  91
  92 static inline int
  93 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
  94 {
  95         int oldval = 0, ret;
  96
  97         if (!access_ok(uaddr, sizeof(u32)))
  98                 return -EFAULT;
  99
 100         switch (op) {
 101         case FUTEX_OP_SET:
 102                 __futex_atomic_op(op, "move $1, %z5", ret, oldval, uaddr, oparg);
 103                 break;
 104
 105         case FUTEX_OP_ADD:
 106                 __futex_atomic_op(op, "addu $1, %1, %z5",
 107                                   ret, oldval, uaddr, oparg);
 108                 break;
 109         case FUTEX_OP_OR:
 110                 __futex_atomic_op(op, "or       $1, %1, %z5",
 111                                   ret, oldval, uaddr, oparg);
 112                 break;
 113         case FUTEX_OP_ANDN:
 114                 __futex_atomic_op(op, "and      $1, %1, %z5",
 115                                   ret, oldval, uaddr, ~oparg);
 116                 break;
 117         case FUTEX_OP_XOR:
 118                 __futex_atomic_op(op, "xor      $1, %1, %z5",
 119                                   ret, oldval, uaddr, oparg);
 120                 break;
 121         default:
 122                 ret = -ENOSYS;
 123         }
 124
 125         if (!ret)
 126                 *oval = oldval;
 127
 128         return ret;
 129 }
 130
 131 static inline int
 132 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 133                               u32 oldval, u32 newval)
 134 {
 135         int ret = 0;
 136         u32 val;
 137
 138         if (!access_ok(uaddr, sizeof(u32)))
 139                 return -EFAULT;
 140
 141         if (cpu_has_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) {
 142                 __asm__ __volatile__(
 143                 "# futex_atomic_cmpxchg_inatomic                        \n"
 144                 "       .set    push                                    \n"
 145                 "       .set    noat                                    \n"
 146                 "       .set    push                                    \n"
 147                 "       .set    arch=r4000                              \n"
 148                 "1:     ll      %1, %3                                  \n"
 149                 "       bne     %1, %z4, 3f                             \n"
 150                 "       .set    pop                                     \n"
 151                 "       move    $1, %z5                                 \n"
 152                 "       .set    arch=r4000                              \n"
 153                 "2:     sc      $1, %2                                  \n"
 154                 "       beqzl   $1, 1b                                  \n"
 155                 __stringify(__WEAK_LLSC_MB) "                           \n"
 156                 "3:                                                     \n"
 157                 "       .insn                                           \n"
 158                 "       .set    pop                                     \n"
 159                 "       .section .fixup,\"ax\"                          \n"
 160                 "4:     li      %0, %6                                  \n"
 161                 "       j       3b                                      \n"
 162                 "       .previous                                       \n"
 163                 "       .section __ex_table,\"a\"                       \n"
 164                 "       "__UA_ADDR "\t1b, 4b                            \n"
 165                 "       "__UA_ADDR "\t2b, 4b                            \n"
 166                 "       .previous                                       \n"
 167                 : "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr)
 168                 : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
 169                   "i" (-EFAULT)
 170                 : "memory");
 171         } else if (cpu_has_llsc) {
 172                 __asm__ __volatile__(
 173                 "# futex_atomic_cmpxchg_inatomic                        \n"
 174                 "       .set    push                                    \n"
 175                 "       .set    noat                                    \n"
 176                 "       .set    push                                    \n"
 177                 "       .set    "MIPS_ISA_ARCH_LEVEL"                   \n"
 178                 "       " __SYNC(full, loongson3_war) "                 \n"
 179                 "1:     "user_ll("%1", "%3")"                           \n"
 180                 "       bne     %1, %z4, 3f                             \n"
 181                 "       .set    pop                                     \n"
 182                 "       move    $1, %z5                                 \n"
 183                 "       .set    "MIPS_ISA_ARCH_LEVEL"                   \n"
 184                 "2:     "user_sc("$1", "%2")"                           \n"
 185                 "       beqz    $1, 1b                                  \n"
 186                 "3:     " __SYNC_ELSE(full, loongson3_war, __WEAK_LLSC_MB) "\n"
 187                 "       .insn                                           \n"
 188                 "       .set    pop                                     \n"
 189                 "       .section .fixup,\"ax\"                          \n"
 190                 "4:     li      %0, %6                                  \n"
 191                 "       j       3b                                      \n"
 192                 "       .previous                                       \n"
 193                 "       .section __ex_table,\"a\"                       \n"
 194                 "       "__UA_ADDR "\t1b, 4b                            \n"
 195                 "       "__UA_ADDR "\t2b, 4b                            \n"
 196                 "       .previous                                       \n"
 197                 : "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr)
 198                 : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
 199                   "i" (-EFAULT)
 200                 : "memory");
 201         } else {
 202                 return futex_atomic_cmpxchg_inatomic_local(uval, uaddr, oldval, newval);
 203         }
 204
 205         *uval = val;
 206         return ret;
 207 }
 208
 209 #endif
 210 #endif /* _ASM_FUTEX_H */