arch/s390/include/asm/stacktrace.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_S390_STACKTRACE_H
   3 #define _ASM_S390_STACKTRACE_H
   4
   5 #include <linux/uaccess.h>
   6 #include <linux/ptrace.h>
   7 #include <asm/switch_to.h>
   8
   9 enum stack_type {
  10         STACK_TYPE_UNKNOWN,
  11         STACK_TYPE_TASK,
  12         STACK_TYPE_IRQ,
  13         STACK_TYPE_NODAT,
  14         STACK_TYPE_RESTART,
  15 };
  16
  17 struct stack_info {
  18         enum stack_type type;
  19         unsigned long begin, end;
  20 };
  21
  22 const char *stack_type_name(enum stack_type type);
  23 int get_stack_info(unsigned long sp, struct task_struct *task,
  24                    struct stack_info *info, unsigned long *visit_mask);
  25
  26 static inline bool on_stack(struct stack_info *info,
  27                             unsigned long addr, size_t len)
  28 {
  29         if (info->type == STACK_TYPE_UNKNOWN)
  30                 return false;
  31         if (addr + len < addr)
  32                 return false;
  33         return addr >= info->begin && addr + len <= info->end;
  34 }
  35
  36 static inline unsigned long get_stack_pointer(struct task_struct *task,
  37                                               struct pt_regs *regs)
  38 {
  39         if (regs)
  40                 return (unsigned long) kernel_stack_pointer(regs);
  41         if (task == current)
  42                 return current_stack_pointer();
  43         return (unsigned long) task->thread.ksp;
  44 }
  45
  46 /*
  47  * Stack layout of a C stack frame.
  48  */
  49 #ifndef __PACK_STACK
  50 struct stack_frame {
  51         unsigned long back_chain;
  52         unsigned long empty1[5];
  53         unsigned long gprs[10];
  54         unsigned int  empty2[8];
  55 };
  56 #else
  57 struct stack_frame {
  58         unsigned long empty1[5];
  59         unsigned int  empty2[8];
  60         unsigned long gprs[10];
  61         unsigned long back_chain;
  62 };
  63 #endif
  64
  65 #define CALL_ARGS_0()                                                   \
  66         register unsigned long r2 asm("2")
  67 #define CALL_ARGS_1(arg1)                                               \
  68         register unsigned long r2 asm("2") = (unsigned long)(arg1)
  69 #define CALL_ARGS_2(arg1, arg2)                                         \
  70         CALL_ARGS_1(arg1);                                              \
  71         register unsigned long r3 asm("3") = (unsigned long)(arg2)
  72 #define CALL_ARGS_3(arg1, arg2, arg3)                                   \
  73         CALL_ARGS_2(arg1, arg2);                                        \
  74         register unsigned long r4 asm("4") = (unsigned long)(arg3)
  75 #define CALL_ARGS_4(arg1, arg2, arg3, arg4)                             \
  76         CALL_ARGS_3(arg1, arg2, arg3);                                  \
  77         register unsigned long r4 asm("5") = (unsigned long)(arg4)
  78 #define CALL_ARGS_5(arg1, arg2, arg3, arg4, arg5)                       \
  79         CALL_ARGS_4(arg1, arg2, arg3, arg4);                            \
  80         register unsigned long r4 asm("6") = (unsigned long)(arg5)
  81
  82 #define CALL_FMT_0 "=&d" (r2) :
  83 #define CALL_FMT_1 "+&d" (r2) :
  84 #define CALL_FMT_2 CALL_FMT_1 "d" (r3),
  85 #define CALL_FMT_3 CALL_FMT_2 "d" (r4),
  86 #define CALL_FMT_4 CALL_FMT_3 "d" (r5),
  87 #define CALL_FMT_5 CALL_FMT_4 "d" (r6),
  88
  89 #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory"
  90 #define CALL_CLOBBER_4 CALL_CLOBBER_5
  91 #define CALL_CLOBBER_3 CALL_CLOBBER_4, "5"
  92 #define CALL_CLOBBER_2 CALL_CLOBBER_3, "4"
  93 #define CALL_CLOBBER_1 CALL_CLOBBER_2, "3"
  94 #define CALL_CLOBBER_0 CALL_CLOBBER_1
  95
  96 #define CALL_ON_STACK(fn, stack, nr, args...)                           \
  97 ({                                                                      \
  98         CALL_ARGS_##nr(args);                                           \
  99         unsigned long prev;                                             \
 100                                                                         \
 101         asm volatile(                                                   \
 102                 "       la      %[_prev],0(15)\n"                       \
 103                 "       la      15,0(%[_stack])\n"                      \
 104                 "       stg     %[_prev],%[_bc](15)\n"                  \
 105                 "       brasl   14,%[_fn]\n"                            \
 106                 "       la      15,0(%[_prev])\n"                       \
 107                 : [_prev] "=&a" (prev), CALL_FMT_##nr                   \
 108                   [_stack] "a" (stack),                                 \
 109                   [_bc] "i" (offsetof(struct stack_frame, back_chain)), \
 110                   [_fn] "X" (fn) : CALL_CLOBBER_##nr);                  \
 111         r2;                                                             \
 112 })
 113
 114 #endif /* _ASM_S390_STACKTRACE_H */