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 
10 #ifdef __ASSEMBLY__
11 
12 #define __ASM_EXTABLE_RAW(insn, fixup, type, data)	\
13 	.pushsection	__ex_table, "a";		\
14 	.balign		4;				\
15 	.long		((insn) - .);			\
16 	.long		((fixup) - .);			\
17 	.short		(type);				\
18 	.short		(data);				\
19 	.popsection;
20 
21 	.macro		_asm_extable, insn, fixup
22 	__ASM_EXTABLE_RAW(\insn, \fixup, EX_TYPE_FIXUP, 0)
23 	.endm
24 
25 #else /* __ASSEMBLY__ */
26 
27 #include <linux/bits.h>
28 #include <linux/stringify.h>
29 #include <asm/gpr-num.h>
30 
31 #define __ASM_EXTABLE_RAW(insn, fixup, type, data)	\
32 	".pushsection	__ex_table, \"a\"\n"		\
33 	".balign	4\n"				\
34 	".long		((" insn ") - .)\n"		\
35 	".long		((" fixup ") - .)\n"		\
36 	".short		(" type ")\n"			\
37 	".short		(" data ")\n"			\
38 	".popsection\n"
39 
40 #define _ASM_EXTABLE(insn, fixup)	\
41 	__ASM_EXTABLE_RAW(#insn, #fixup, __stringify(EX_TYPE_FIXUP), "0")
42 
43 #define EX_DATA_REG_ERR_SHIFT	0
44 #define EX_DATA_REG_ERR		GENMASK(4, 0)
45 #define EX_DATA_REG_ZERO_SHIFT	5
46 #define EX_DATA_REG_ZERO	GENMASK(9, 5)
47 
48 #define EX_DATA_REG(reg, gpr)						\
49 	"((.L__gpr_num_" #gpr ") << " __stringify(EX_DATA_REG_##reg##_SHIFT) ")"
50 
51 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)		\
52 	__DEFINE_ASM_GPR_NUMS						\
53 	__ASM_EXTABLE_RAW(#insn, #fixup, 				\
54 			  __stringify(EX_TYPE_UACCESS_ERR_ZERO),	\
55 			  "("						\
56 			    EX_DATA_REG(ERR, err) " | "			\
57 			    EX_DATA_REG(ZERO, zero)			\
58 			  ")")
59 
60 #define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err)			\
61 	_ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)
62 
63 #endif /* __ASSEMBLY__ */
64 
65 #endif /* __ASM_ASM_EXTABLE_H */
66