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