arch/s390/include/asm/runtime-const.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_S390_RUNTIME_CONST_H
   3 #define _ASM_S390_RUNTIME_CONST_H
   4
   5 #include <linux/uaccess.h>
   6
   7 #define runtime_const_ptr(sym)                                  \
   8 ({                                                              \
   9         typeof(sym) __ret;                                      \
  10                                                                 \
  11         asm_inline(                                             \
  12                 "0:     iihf    %[__ret],%[c1]\n"               \
  13                 "       iilf    %[__ret],%[c2]\n"               \
  14                 ".pushsection runtime_ptr_" #sym ",\"a\"\n"     \
  15                 ".long 0b - .\n"                                \
  16                 ".popsection"                                   \
  17                 : [__ret] "=d" (__ret)                          \
  18                 : [c1] "i" (0x01234567UL),                      \
  19                   [c2] "i" (0x89abcdefUL));                     \
  20         __ret;                                                  \
  21 })
  22
  23 #define runtime_const_shift_right_32(val, sym)                  \
  24 ({                                                              \
  25         unsigned int __ret = (val);                             \
  26                                                                 \
  27         asm_inline(                                             \
  28                 "0:     srl     %[__ret],12\n"                  \
  29                 ".pushsection runtime_shift_" #sym ",\"a\"\n"   \
  30                 ".long 0b - .\n"                                \
  31                 ".popsection"                                   \
  32                 : [__ret] "+d" (__ret));                        \
  33         __ret;                                                  \
  34 })
  35
  36 #define runtime_const_init(type, sym) do {                      \
  37         extern s32 __start_runtime_##type##_##sym[];            \
  38         extern s32 __stop_runtime_##type##_##sym[];             \
  39                                                                 \
  40         runtime_const_fixup(__runtime_fixup_##type,             \
  41                             (unsigned long)(sym),               \
  42                             __start_runtime_##type##_##sym,     \
  43                             __stop_runtime_##type##_##sym);     \
  44 } while (0)
  45
  46 /* 32-bit immediate for iihf and iilf in bits in I2 field */
  47 static inline void __runtime_fixup_32(u32 *p, unsigned int val)
  48 {
  49         s390_kernel_write(p, &val, sizeof(val));
  50 }
  51
  52 static inline void __runtime_fixup_ptr(void *where, unsigned long val)
  53 {
  54         __runtime_fixup_32(where + 2, val >> 32);
  55         __runtime_fixup_32(where + 8, val);
  56 }
  57
  58 /* Immediate value is lower 12 bits of D2 field of srl */
  59 static inline void __runtime_fixup_shift(void *where, unsigned long val)
  60 {
  61         u32 insn = *(u32 *)where;
  62
  63         insn &= 0xfffff000;
  64         insn |= (val & 63);
  65         s390_kernel_write(where, &insn, sizeof(insn));
  66 }
  67
  68 static inline void runtime_const_fixup(void (*fn)(void *, unsigned long),
  69                                        unsigned long val, s32 *start, s32 *end)
  70 {
  71         while (start < end) {
  72                 fn(*start + (void *)start, val);
  73                 start++;
  74         }
  75 }
  76
  77 #endif /* _ASM_S390_RUNTIME_CONST_H */