1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_GENERIC_ERROR_INJECTION_H
3 #define _ASM_GENERIC_ERROR_INJECTION_H
4 
5 #if defined(__KERNEL__) && !defined(__ASSEMBLY__)
6 enum {
7 	EI_ETYPE_NULL,		/* Return NULL if failure */
8 	EI_ETYPE_ERRNO,		/* Return -ERRNO if failure */
9 	EI_ETYPE_ERRNO_NULL,	/* Return -ERRNO or NULL if failure */
10 	EI_ETYPE_TRUE,		/* Return true if failure */
11 };
12 
13 struct error_injection_entry {
14 	unsigned long	addr;
15 	int		etype;
16 };
17 
18 struct pt_regs;
19 
20 #ifdef CONFIG_FUNCTION_ERROR_INJECTION
21 /*
22  * Whitelist generating macro. Specify functions which can be error-injectable
23  * using this macro. If you unsure what is required for the error-injectable
24  * functions, please read Documentation/fault-injection/fault-injection.rst
25  * 'Error Injectable Functions' section.
26  */
27 #define ALLOW_ERROR_INJECTION(fname, _etype)				\
28 static struct error_injection_entry __used				\
29 	__section("_error_injection_whitelist")				\
30 	_eil_addr_##fname = {						\
31 		.addr = (unsigned long)fname,				\
32 		.etype = EI_ETYPE_##_etype,				\
33 	}
34 
35 void override_function_with_return(struct pt_regs *regs);
36 #else
37 #define ALLOW_ERROR_INJECTION(fname, _etype)
38 
override_function_with_return(struct pt_regs * regs)39 static inline void override_function_with_return(struct pt_regs *regs) { }
40 #endif
41 #endif
42 
43 #endif /* _ASM_GENERIC_ERROR_INJECTION_H */
44