1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 #ifndef __ASM_ASM_EXTABLE_H 3 #define __ASM_ASM_EXTABLE_H 4 5 #include <linux/bits.h> 6 #include <asm/gpr-num.h> 7 8 #define EX_TYPE_NONE 0 9 #define EX_TYPE_FIXUP 1 10 #define EX_TYPE_BPF 2 11 #define EX_TYPE_UACCESS_ERR_ZERO 3 12 #define EX_TYPE_KACCESS_ERR_ZERO 4 13 #define EX_TYPE_LOAD_UNALIGNED_ZEROPAD 5 14 15 /* Data fields for EX_TYPE_UACCESS_ERR_ZERO */ 16 #define EX_DATA_REG_ERR_SHIFT 0 17 #define EX_DATA_REG_ERR GENMASK(4, 0) 18 #define EX_DATA_REG_ZERO_SHIFT 5 19 #define EX_DATA_REG_ZERO GENMASK(9, 5) 20 21 /* Data fields for EX_TYPE_LOAD_UNALIGNED_ZEROPAD */ 22 #define EX_DATA_REG_DATA_SHIFT 0 23 #define EX_DATA_REG_DATA GENMASK(4, 0) 24 #define EX_DATA_REG_ADDR_SHIFT 5 25 #define EX_DATA_REG_ADDR GENMASK(9, 5) 26 27 #ifdef __ASSEMBLY__ 28 29 #define __ASM_EXTABLE_RAW(insn, fixup, type, data) \ 30 .pushsection __ex_table, "a"; \ 31 .align 2; \ 32 .long ((insn) - .); \ 33 .long ((fixup) - .); \ 34 .short (type); \ 35 .short (data); \ 36 .popsection; 37 38 #define _ASM_EXTABLE(insn, fixup) \ 39 __ASM_EXTABLE_RAW(insn, fixup, EX_TYPE_FIXUP, 0) 40 41 #define EX_DATA_REG(reg, gpr) \ 42 (.L__gpr_num_##gpr << EX_DATA_REG_##reg##_SHIFT) 43 44 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero) \ 45 __ASM_EXTABLE_RAW(insn, fixup, \ 46 EX_TYPE_UACCESS_ERR_ZERO, \ 47 ( \ 48 EX_DATA_REG(ERR, err) | \ 49 EX_DATA_REG(ZERO, zero) \ 50 )) 51 52 #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err) \ 53 _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, wzr) 54 55 #define _ASM_EXTABLE_UACCESS(insn, fixup) \ 56 _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, wzr, wzr) 57 58 /* 59 * Create an exception table entry for `insn`, which will branch to `fixup` 60 * when an unhandled fault is taken. 61 */ 62 .macro _asm_extable, insn, fixup 63 _ASM_EXTABLE(\insn, \fixup) 64 .endm 65 66 /* 67 * Create an exception table entry for `insn` if `fixup` is provided. Otherwise 68 * do nothing. 69 */ 70 .macro _cond_extable, insn, fixup 71 .ifnc \fixup, 72 _asm_extable \insn, \fixup 73 .endif 74 .endm 75 76 #else /* __ASSEMBLY__ */ 77 78 #include <linux/stringify.h> 79 80 #define __ASM_EXTABLE_RAW(insn, fixup, type, data) \ 81 ".pushsection __ex_table, \"a\"\n" \ 82 ".align 2\n" \ 83 ".long ((" insn ") - .)\n" \ 84 ".long ((" fixup ") - .)\n" \ 85 ".short (" type ")\n" \ 86 ".short (" data ")\n" \ 87 ".popsection\n" 88 89 #define _ASM_EXTABLE(insn, fixup) \ 90 __ASM_EXTABLE_RAW(#insn, #fixup, __stringify(EX_TYPE_FIXUP), "0") 91 92 #define EX_DATA_REG(reg, gpr) \ 93 "((.L__gpr_num_" #gpr ") << " __stringify(EX_DATA_REG_##reg##_SHIFT) ")" 94 95 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero) \ 96 __DEFINE_ASM_GPR_NUMS \ 97 __ASM_EXTABLE_RAW(#insn, #fixup, \ 98 __stringify(EX_TYPE_UACCESS_ERR_ZERO), \ 99 "(" \ 100 EX_DATA_REG(ERR, err) " | " \ 101 EX_DATA_REG(ZERO, zero) \ 102 ")") 103 104 #define _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, zero) \ 105 __DEFINE_ASM_GPR_NUMS \ 106 __ASM_EXTABLE_RAW(#insn, #fixup, \ 107 __stringify(EX_TYPE_KACCESS_ERR_ZERO), \ 108 "(" \ 109 EX_DATA_REG(ERR, err) " | " \ 110 EX_DATA_REG(ZERO, zero) \ 111 ")") 112 113 #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err) \ 114 _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, wzr) 115 116 #define _ASM_EXTABLE_UACCESS(insn, fixup) \ 117 _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, wzr, wzr) 118 119 #define _ASM_EXTABLE_KACCESS_ERR(insn, fixup, err) \ 120 _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, wzr) 121 122 #define _ASM_EXTABLE_LOAD_UNALIGNED_ZEROPAD(insn, fixup, data, addr) \ 123 __DEFINE_ASM_GPR_NUMS \ 124 __ASM_EXTABLE_RAW(#insn, #fixup, \ 125 __stringify(EX_TYPE_LOAD_UNALIGNED_ZEROPAD), \ 126 "(" \ 127 EX_DATA_REG(DATA, data) " | " \ 128 EX_DATA_REG(ADDR, addr) \ 129 ")") 130 131 #endif /* __ASSEMBLY__ */ 132 133 #endif /* __ASM_ASM_EXTABLE_H */ 134