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