include/asm/inst.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 #ifndef _ASM_POWERPC_INST_H
0003 #define _ASM_POWERPC_INST_H
0004
0005 #include <asm/ppc-opcode.h>
0006 #include <asm/reg.h>
0007 #include <asm/disassemble.h>
0008 #include <asm/uaccess.h>
0009
0010 #define ___get_user_instr(gu_op, dest, ptr)             \
0011 ({                                  \
0012     long __gui_ret;                         \
0013     u32 __user *__gui_ptr = (u32 __user *)ptr;          \
0014     ppc_inst_t __gui_inst;                      \
0015     unsigned int __prefix, __suffix;                \
0016                                     \
0017     __chk_user_ptr(ptr);                        \
0018     __gui_ret = gu_op(__prefix, __gui_ptr);             \
0019     if (__gui_ret == 0) {                       \
0020         if (IS_ENABLED(CONFIG_PPC64) && (__prefix >> 26) == OP_PREFIX) { \
0021             __gui_ret = gu_op(__suffix, __gui_ptr + 1); \
0022             __gui_inst = ppc_inst_prefix(__prefix, __suffix); \
0023         } else {                        \
0024             __gui_inst = ppc_inst(__prefix);        \
0025         }                           \
0026         if (__gui_ret == 0)                 \
0027             (dest) = __gui_inst;                \
0028     }                               \
0029     __gui_ret;                          \
0030 })
0031
0032 #define get_user_instr(x, ptr) ___get_user_instr(get_user, x, ptr)
0033
0034 #define __get_user_instr(x, ptr) ___get_user_instr(__get_user, x, ptr)
0035
0036 /*
0037  * Instruction data type for POWER
0038  */
0039
0040 #if defined(CONFIG_PPC64) || defined(__CHECKER__)
0041 static inline u32 ppc_inst_val(ppc_inst_t x)
0042 {
0043     return x.val;
0044 }
0045
0046 #define ppc_inst(x) ((ppc_inst_t){ .val = (x) })
0047
0048 #else
0049 static inline u32 ppc_inst_val(ppc_inst_t x)
0050 {
0051     return x;
0052 }
0053 #define ppc_inst(x) (x)
0054 #endif
0055
0056 static inline int ppc_inst_primary_opcode(ppc_inst_t x)
0057 {
0058     return ppc_inst_val(x) >> 26;
0059 }
0060
0061 #ifdef CONFIG_PPC64
0062 #define ppc_inst_prefix(x, y) ((ppc_inst_t){ .val = (x), .suffix = (y) })
0063
0064 static inline u32 ppc_inst_suffix(ppc_inst_t x)
0065 {
0066     return x.suffix;
0067 }
0068
0069 #else
0070 #define ppc_inst_prefix(x, y) ((void)y, ppc_inst(x))
0071
0072 static inline u32 ppc_inst_suffix(ppc_inst_t x)
0073 {
0074     return 0;
0075 }
0076
0077 #endif /* CONFIG_PPC64 */
0078
0079 static inline ppc_inst_t ppc_inst_read(const u32 *ptr)
0080 {
0081     if (IS_ENABLED(CONFIG_PPC64) && (*ptr >> 26) == OP_PREFIX)
0082         return ppc_inst_prefix(*ptr, *(ptr + 1));
0083     else
0084         return ppc_inst(*ptr);
0085 }
0086
0087 static inline bool ppc_inst_prefixed(ppc_inst_t x)
0088 {
0089     return IS_ENABLED(CONFIG_PPC64) && ppc_inst_primary_opcode(x) == OP_PREFIX;
0090 }
0091
0092 static inline ppc_inst_t ppc_inst_swab(ppc_inst_t x)
0093 {
0094     return ppc_inst_prefix(swab32(ppc_inst_val(x)), swab32(ppc_inst_suffix(x)));
0095 }
0096
0097 static inline bool ppc_inst_equal(ppc_inst_t x, ppc_inst_t y)
0098 {
0099     if (ppc_inst_val(x) != ppc_inst_val(y))
0100         return false;
0101     if (!ppc_inst_prefixed(x))
0102         return true;
0103     return ppc_inst_suffix(x) == ppc_inst_suffix(y);
0104 }
0105
0106 static inline int ppc_inst_len(ppc_inst_t x)
0107 {
0108     return ppc_inst_prefixed(x) ? 8 : 4;
0109 }
0110
0111 /*
0112  * Return the address of the next instruction, if the instruction @value was
0113  * located at @location.
0114  */
0115 static inline u32 *ppc_inst_next(u32 *location, u32 *value)
0116 {
0117     ppc_inst_t tmp;
0118
0119     tmp = ppc_inst_read(value);
0120
0121     return (void *)location + ppc_inst_len(tmp);
0122 }
0123
0124 static inline unsigned long ppc_inst_as_ulong(ppc_inst_t x)
0125 {
0126     if (IS_ENABLED(CONFIG_PPC32))
0127         return ppc_inst_val(x);
0128     else if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
0129         return (u64)ppc_inst_suffix(x) << 32 | ppc_inst_val(x);
0130     else
0131         return (u64)ppc_inst_val(x) << 32 | ppc_inst_suffix(x);
0132 }
0133
0134 static inline void ppc_inst_write(u32 *ptr, ppc_inst_t x)
0135 {
0136     if (!ppc_inst_prefixed(x))
0137         *ptr = ppc_inst_val(x);
0138     else
0139         *(u64 *)ptr = ppc_inst_as_ulong(x);
0140 }
0141
0142 static inline int __copy_inst_from_kernel_nofault(ppc_inst_t *inst, u32 *src)
0143 {
0144     unsigned int val, suffix;
0145
0146 /* See https://github.com/ClangBuiltLinux/linux/issues/1521 */
0147 #if defined(CONFIG_CC_IS_CLANG) && CONFIG_CLANG_VERSION < 140000
0148     val = suffix = 0;
0149 #endif
0150     __get_kernel_nofault(&val, src, u32, Efault);
0151     if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) {
0152         __get_kernel_nofault(&suffix, src + 1, u32, Efault);
0153         *inst = ppc_inst_prefix(val, suffix);
0154     } else {
0155         *inst = ppc_inst(val);
0156     }
0157     return 0;
0158 Efault:
0159     return -EFAULT;
0160 }
0161
0162 static inline int copy_inst_from_kernel_nofault(ppc_inst_t *inst, u32 *src)
0163 {
0164     if (unlikely(!is_kernel_addr((unsigned long)src)))
0165         return -ERANGE;
0166
0167     return __copy_inst_from_kernel_nofault(inst, src);
0168 }
0169
0170 #endif /* _ASM_POWERPC_INST_H */