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