arch/x86/include/asm/unwind.h

   1 #ifndef _ASM_X86_UNWIND_H
   2 #define _ASM_X86_UNWIND_H
   3
   4 #include <linux/sched.h>
   5 #include <linux/ftrace.h>
   6 #include <asm/ptrace.h>
   7 #include <asm/stacktrace.h>
   8
   9 struct unwind_state {
  10         struct stack_info stack_info;
  11         unsigned long stack_mask;
  12         struct task_struct *task;
  13         int graph_idx;
  14         bool error;
  15 #if defined(CONFIG_ORC_UNWINDER)
  16         bool signal, full_regs;
  17         unsigned long sp, bp, ip;
  18         struct pt_regs *regs;
  19 #elif defined(CONFIG_FRAME_POINTER_UNWINDER)
  20         bool got_irq;
  21         unsigned long *bp, *orig_sp, ip;
  22         struct pt_regs *regs;
  23 #else
  24         unsigned long *sp;
  25 #endif
  26 };
  27
  28 void __unwind_start(struct unwind_state *state, struct task_struct *task,
  29                     struct pt_regs *regs, unsigned long *first_frame);
  30 bool unwind_next_frame(struct unwind_state *state);
  31 unsigned long unwind_get_return_address(struct unwind_state *state);
  32 unsigned long *unwind_get_return_address_ptr(struct unwind_state *state);
  33
  34 static inline bool unwind_done(struct unwind_state *state)
  35 {
  36         return state->stack_info.type == STACK_TYPE_UNKNOWN;
  37 }
  38
  39 static inline bool unwind_error(struct unwind_state *state)
  40 {
  41         return state->error;
  42 }
  43
  44 static inline
  45 void unwind_start(struct unwind_state *state, struct task_struct *task,
  46                   struct pt_regs *regs, unsigned long *first_frame)
  47 {
  48         first_frame = first_frame ? : get_stack_pointer(task, regs);
  49
  50         __unwind_start(state, task, regs, first_frame);
  51 }
  52
  53 #if defined(CONFIG_ORC_UNWINDER) || defined(CONFIG_FRAME_POINTER_UNWINDER)
  54 static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
  55 {
  56         if (unwind_done(state))
  57                 return NULL;
  58
  59         return state->regs;
  60 }
  61 #else
  62 static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state)
  63 {
  64         return NULL;
  65 }
  66 #endif
  67
  68 #ifdef CONFIG_ORC_UNWINDER
  69 void unwind_init(void);
  70 void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
  71                         void *orc, size_t orc_size);
  72 #else
  73 static inline void unwind_init(void) {}
  74 static inline
  75 void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
  76                         void *orc, size_t orc_size) {}
  77 #endif
  78
  79 /*
  80  * This disables KASAN checking when reading a value from another task's stack,
  81  * since the other task could be running on another CPU and could have poisoned
  82  * the stack in the meantime.
  83  */
  84 #define READ_ONCE_TASK_STACK(task, x)                   \
  85 ({                                                      \
  86         unsigned long val;                              \
  87         if (task == current)                            \
  88                 val = READ_ONCE(x);                     \
  89         else                                            \
  90                 val = READ_ONCE_NOCHECK(x);             \
  91         val;                                            \
  92 })
  93
  94 static inline bool task_on_another_cpu(struct task_struct *task)
  95 {
  96 #ifdef CONFIG_SMP
  97         return task != current && task->on_cpu;
  98 #else
  99         return false;
 100 #endif
 101 }
 102
 103 #endif /* _ASM_X86_UNWIND_H */