1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_FAULT_INJECT_H
3 #define _LINUX_FAULT_INJECT_H
4 
5 #ifdef CONFIG_FAULT_INJECTION
6 
7 #include <linux/types.h>
8 #include <linux/debugfs.h>
9 #include <linux/ratelimit.h>
10 #include <linux/atomic.h>
11 
12 /*
13  * For explanation of the elements of this struct, see
14  * Documentation/fault-injection/fault-injection.rst
15  */
16 struct fault_attr {
17 	unsigned long probability;
18 	unsigned long interval;
19 	atomic_t times;
20 	atomic_t space;
21 	unsigned long verbose;
22 	bool task_filter;
23 	unsigned long stacktrace_depth;
24 	unsigned long require_start;
25 	unsigned long require_end;
26 	unsigned long reject_start;
27 	unsigned long reject_end;
28 
29 	unsigned long count;
30 	struct ratelimit_state ratelimit_state;
31 	struct dentry *dname;
32 };
33 
34 enum fault_flags {
35 	FAULT_NOWARN =	1 << 0,
36 };
37 
38 #define FAULT_ATTR_INITIALIZER {					\
39 		.interval = 1,						\
40 		.times = ATOMIC_INIT(1),				\
41 		.require_end = ULONG_MAX,				\
42 		.stacktrace_depth = 32,					\
43 		.ratelimit_state = RATELIMIT_STATE_INIT_DISABLED,	\
44 		.verbose = 2,						\
45 		.dname = NULL,						\
46 	}
47 
48 #define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER
49 int setup_fault_attr(struct fault_attr *attr, char *str);
50 bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags);
51 bool should_fail(struct fault_attr *attr, ssize_t size);
52 
53 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
54 
55 struct dentry *fault_create_debugfs_attr(const char *name,
56 			struct dentry *parent, struct fault_attr *attr);
57 
58 #else /* CONFIG_FAULT_INJECTION_DEBUG_FS */
59 
fault_create_debugfs_attr(const char * name,struct dentry * parent,struct fault_attr * attr)60 static inline struct dentry *fault_create_debugfs_attr(const char *name,
61 			struct dentry *parent, struct fault_attr *attr)
62 {
63 	return ERR_PTR(-ENODEV);
64 }
65 
66 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
67 
68 #endif /* CONFIG_FAULT_INJECTION */
69 
70 struct kmem_cache;
71 
72 bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order);
73 
74 int should_failslab(struct kmem_cache *s, gfp_t gfpflags);
75 #ifdef CONFIG_FAILSLAB
76 extern bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags);
77 #else
__should_failslab(struct kmem_cache * s,gfp_t gfpflags)78 static inline bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
79 {
80 	return false;
81 }
82 #endif /* CONFIG_FAILSLAB */
83 
84 #endif /* _LINUX_FAULT_INJECT_H */
85