include/linux/fault-inject.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_FAULT_INJECT_H
   3 #define _LINUX_FAULT_INJECT_H
   4
   5 #include <linux/err.h>
   6 #include <linux/types.h>
   7
   8 struct dentry;
   9 struct kmem_cache;
  10
  11 #ifdef CONFIG_FAULT_INJECTION
  12
  13 #include <linux/atomic.h>
  14 #include <linux/configfs.h>
  15 #include <linux/ratelimit.h>
  16
  17 /*
  18  * For explanation of the elements of this struct, see
  19  * Documentation/fault-injection/fault-injection.rst
  20  */
  21 struct fault_attr {
  22         unsigned long probability;
  23         unsigned long interval;
  24         atomic_t times;
  25         atomic_t space;
  26         unsigned long verbose;
  27         bool task_filter;
  28         unsigned long stacktrace_depth;
  29         unsigned long require_start;
  30         unsigned long require_end;
  31         unsigned long reject_start;
  32         unsigned long reject_end;
  33
  34         unsigned long count;
  35         struct ratelimit_state ratelimit_state;
  36         struct dentry *dname;
  37 };
  38
  39 enum fault_flags {
  40         FAULT_NOWARN =  1 << 0,
  41 };
  42
  43 #define FAULT_ATTR_INITIALIZER {                                        \
  44                 .interval = 1,                                          \
  45                 .times = ATOMIC_INIT(1),                                \
  46                 .require_end = ULONG_MAX,                               \
  47                 .stacktrace_depth = 32,                                 \
  48                 .ratelimit_state = RATELIMIT_STATE_INIT_DISABLED,       \
  49                 .verbose = 2,                                           \
  50                 .dname = NULL,                                          \
  51         }
  52
  53 #define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER
  54 int setup_fault_attr(struct fault_attr *attr, char *str);
  55 bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags);
  56 bool should_fail(struct fault_attr *attr, ssize_t size);
  57
  58 #else /* CONFIG_FAULT_INJECTION */
  59
  60 struct fault_attr {
  61 };
  62
  63 #define DECLARE_FAULT_ATTR(name) struct fault_attr name = {}
  64
  65 static inline int setup_fault_attr(struct fault_attr *attr, char *str)
  66 {
  67         return 0; /* Note: 0 means error for __setup() handlers! */
  68 }
  69 static inline bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags)
  70 {
  71         return false;
  72 }
  73 static inline bool should_fail(struct fault_attr *attr, ssize_t size)
  74 {
  75         return false;
  76 }
  77
  78 #endif /* CONFIG_FAULT_INJECTION */
  79
  80 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
  81
  82 struct dentry *fault_create_debugfs_attr(const char *name,
  83                         struct dentry *parent, struct fault_attr *attr);
  84
  85 #else /* CONFIG_FAULT_INJECTION_DEBUG_FS */
  86
  87 static inline struct dentry *fault_create_debugfs_attr(const char *name,
  88                         struct dentry *parent, struct fault_attr *attr)
  89 {
  90         return ERR_PTR(-ENODEV);
  91 }
  92
  93 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
  94
  95 #ifdef CONFIG_FAULT_INJECTION_CONFIGFS
  96
  97 struct fault_config {
  98         struct fault_attr attr;
  99         struct config_group group;
 100 };
 101
 102 void fault_config_init(struct fault_config *config, const char *name);
 103
 104 #else /* CONFIG_FAULT_INJECTION_CONFIGFS */
 105
 106 struct fault_config {
 107 };
 108
 109 static inline void fault_config_init(struct fault_config *config,
 110                         const char *name)
 111 {
 112 }
 113
 114 #endif /* CONFIG_FAULT_INJECTION_CONFIGFS */
 115
 116 #ifdef CONFIG_FAIL_PAGE_ALLOC
 117 bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order);
 118 #else
 119 static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
 120 {
 121         return false;
 122 }
 123 #endif /* CONFIG_FAIL_PAGE_ALLOC */
 124
 125 #ifdef CONFIG_FAILSLAB
 126 int should_failslab(struct kmem_cache *s, gfp_t gfpflags);
 127 #else
 128 static inline int should_failslab(struct kmem_cache *s, gfp_t gfpflags)
 129 {
 130         return false;
 131 }
 132 #endif /* CONFIG_FAILSLAB */
 133
 134 #endif /* _LINUX_FAULT_INJECT_H */