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 __always_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 /* 66 * Unlike current_stack_pointer() which simply returns current value of %r15 67 * current_frame_address() returns function stack frame address, which matches 68 * %r15 upon function invocation. It may differ from %r15 later if function 69 * allocates stack for local variables or new stack frame to call other 70 * functions. 71 */ 72 #define current_frame_address() \ 73 ((unsigned long)__builtin_frame_address(0) - \ 74 offsetof(struct stack_frame, back_chain)) 75 76 #define CALL_ARGS_0() \ 77 register unsigned long r2 asm("2") 78 #define CALL_ARGS_1(arg1) \ 79 register unsigned long r2 asm("2") = (unsigned long)(arg1) 80 #define CALL_ARGS_2(arg1, arg2) \ 81 CALL_ARGS_1(arg1); \ 82 register unsigned long r3 asm("3") = (unsigned long)(arg2) 83 #define CALL_ARGS_3(arg1, arg2, arg3) \ 84 CALL_ARGS_2(arg1, arg2); \ 85 register unsigned long r4 asm("4") = (unsigned long)(arg3) 86 #define CALL_ARGS_4(arg1, arg2, arg3, arg4) \ 87 CALL_ARGS_3(arg1, arg2, arg3); \ 88 register unsigned long r4 asm("5") = (unsigned long)(arg4) 89 #define CALL_ARGS_5(arg1, arg2, arg3, arg4, arg5) \ 90 CALL_ARGS_4(arg1, arg2, arg3, arg4); \ 91 register unsigned long r4 asm("6") = (unsigned long)(arg5) 92 93 #define CALL_FMT_0 "=&d" (r2) : 94 #define CALL_FMT_1 "+&d" (r2) : 95 #define CALL_FMT_2 CALL_FMT_1 "d" (r3), 96 #define CALL_FMT_3 CALL_FMT_2 "d" (r4), 97 #define CALL_FMT_4 CALL_FMT_3 "d" (r5), 98 #define CALL_FMT_5 CALL_FMT_4 "d" (r6), 99 100 #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory" 101 #define CALL_CLOBBER_4 CALL_CLOBBER_5 102 #define CALL_CLOBBER_3 CALL_CLOBBER_4, "5" 103 #define CALL_CLOBBER_2 CALL_CLOBBER_3, "4" 104 #define CALL_CLOBBER_1 CALL_CLOBBER_2, "3" 105 #define CALL_CLOBBER_0 CALL_CLOBBER_1 106 107 #define CALL_ON_STACK(fn, stack, nr, args...) \ 108 ({ \ 109 unsigned long frame = current_frame_address(); \ 110 CALL_ARGS_##nr(args); \ 111 unsigned long prev; \ 112 \ 113 asm volatile( \ 114 " la %[_prev],0(15)\n" \ 115 " lg 15,%[_stack]\n" \ 116 " stg %[_frame],%[_bc](15)\n" \ 117 " brasl 14,%[_fn]\n" \ 118 " la 15,0(%[_prev])\n" \ 119 : [_prev] "=&a" (prev), CALL_FMT_##nr \ 120 [_stack] "R" (stack), \ 121 [_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 122 [_frame] "d" (frame), \ 123 [_fn] "X" (fn) : CALL_CLOBBER_##nr); \ 124 r2; \ 125 }) 126 127 #define CALL_ON_STACK_NORETURN(fn, stack) \ 128 ({ \ 129 asm volatile( \ 130 " la 15,0(%[_stack])\n" \ 131 " xc %[_bc](8,15),%[_bc](15)\n" \ 132 " brasl 14,%[_fn]\n" \ 133 ::[_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 134 [_stack] "a" (stack), [_fn] "X" (fn)); \ 135 BUG(); \ 136 }) 137 138 #endif /* _ASM_S390_STACKTRACE_H */ 139