1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_STACKTRACE_H
3 #define _ASM_STACKTRACE_H
4
5 #include <asm/ptrace.h>
6 #include <asm/asm.h>
7 #include <linux/stringify.h>
8
9 #ifdef CONFIG_KALLSYMS
10 extern int raw_show_trace;
11 extern unsigned long unwind_stack(struct task_struct *task, unsigned long *sp,
12 unsigned long pc, unsigned long *ra);
13 extern unsigned long unwind_stack_by_address(unsigned long stack_page,
14 unsigned long *sp,
15 unsigned long pc,
16 unsigned long *ra);
17 #else
18 #define raw_show_trace 1
unwind_stack(struct task_struct * task,unsigned long * sp,unsigned long pc,unsigned long * ra)19 static inline unsigned long unwind_stack(struct task_struct *task,
20 unsigned long *sp, unsigned long pc, unsigned long *ra)
21 {
22 return 0;
23 }
24 #endif
25
26 #define STR_PTR_LA __stringify(PTR_LA)
27 #define STR_LONG_S __stringify(LONG_S)
28 #define STR_LONG_L __stringify(LONG_L)
29 #define STR_LONGSIZE __stringify(LONGSIZE)
30
31 #define STORE_ONE_REG(r) \
32 STR_LONG_S " $" __stringify(r)",("STR_LONGSIZE"*"__stringify(r)")(%1)\n\t"
33
prepare_frametrace(struct pt_regs * regs)34 static __always_inline void prepare_frametrace(struct pt_regs *regs)
35 {
36 #ifndef CONFIG_KALLSYMS
37 /*
38 * Remove any garbage that may be in regs (specially func
39 * addresses) to avoid show_raw_backtrace() to report them
40 */
41 memset(regs, 0, sizeof(*regs));
42 #endif
43 __asm__ __volatile__(
44 ".set push\n\t"
45 ".set noat\n\t"
46 /* Store $1 so we can use it */
47 STR_LONG_S " $1,"STR_LONGSIZE"(%1)\n\t"
48 /* Store the PC */
49 "1: " STR_PTR_LA " $1, 1b\n\t"
50 STR_LONG_S " $1,%0\n\t"
51 STORE_ONE_REG(2)
52 STORE_ONE_REG(3)
53 STORE_ONE_REG(4)
54 STORE_ONE_REG(5)
55 STORE_ONE_REG(6)
56 STORE_ONE_REG(7)
57 STORE_ONE_REG(8)
58 STORE_ONE_REG(9)
59 STORE_ONE_REG(10)
60 STORE_ONE_REG(11)
61 STORE_ONE_REG(12)
62 STORE_ONE_REG(13)
63 STORE_ONE_REG(14)
64 STORE_ONE_REG(15)
65 STORE_ONE_REG(16)
66 STORE_ONE_REG(17)
67 STORE_ONE_REG(18)
68 STORE_ONE_REG(19)
69 STORE_ONE_REG(20)
70 STORE_ONE_REG(21)
71 STORE_ONE_REG(22)
72 STORE_ONE_REG(23)
73 STORE_ONE_REG(24)
74 STORE_ONE_REG(25)
75 STORE_ONE_REG(26)
76 STORE_ONE_REG(27)
77 STORE_ONE_REG(28)
78 STORE_ONE_REG(29)
79 STORE_ONE_REG(30)
80 STORE_ONE_REG(31)
81 /* Restore $1 */
82 STR_LONG_L " $1,"STR_LONGSIZE"(%1)\n\t"
83 ".set pop\n\t"
84 : "=m" (regs->cp0_epc)
85 : "r" (regs->regs)
86 : "memory");
87 }
88
89 #endif /* _ASM_STACKTRACE_H */
90