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 STACK_TYPE_MCCK, 16 }; 17 18 struct stack_info { 19 enum stack_type type; 20 unsigned long begin, end; 21 }; 22 23 const char *stack_type_name(enum stack_type type); 24 int get_stack_info(unsigned long sp, struct task_struct *task, 25 struct stack_info *info, unsigned long *visit_mask); 26 27 static inline bool on_stack(struct stack_info *info, 28 unsigned long addr, size_t len) 29 { 30 if (info->type == STACK_TYPE_UNKNOWN) 31 return false; 32 if (addr + len < addr) 33 return false; 34 return addr >= info->begin && addr + len <= info->end; 35 } 36 37 static __always_inline unsigned long get_stack_pointer(struct task_struct *task, 38 struct pt_regs *regs) 39 { 40 if (regs) 41 return (unsigned long) kernel_stack_pointer(regs); 42 if (task == current) 43 return current_stack_pointer(); 44 return (unsigned long) task->thread.ksp; 45 } 46 47 /* 48 * Stack layout of a C stack frame. 49 */ 50 #ifndef __PACK_STACK 51 struct stack_frame { 52 unsigned long back_chain; 53 unsigned long empty1[5]; 54 unsigned long gprs[10]; 55 unsigned int empty2[8]; 56 }; 57 #else 58 struct stack_frame { 59 unsigned long empty1[5]; 60 unsigned int empty2[8]; 61 unsigned long gprs[10]; 62 unsigned long back_chain; 63 }; 64 #endif 65 66 /* 67 * Unlike current_stack_pointer() which simply returns current value of %r15 68 * current_frame_address() returns function stack frame address, which matches 69 * %r15 upon function invocation. It may differ from %r15 later if function 70 * allocates stack for local variables or new stack frame to call other 71 * functions. 72 */ 73 #define current_frame_address() \ 74 ((unsigned long)__builtin_frame_address(0) - \ 75 offsetof(struct stack_frame, back_chain)) 76 77 #define CALL_ARGS_0() \ 78 register unsigned long r2 asm("2") 79 #define CALL_ARGS_1(arg1) \ 80 register unsigned long r2 asm("2") = (unsigned long)(arg1) 81 #define CALL_ARGS_2(arg1, arg2) \ 82 CALL_ARGS_1(arg1); \ 83 register unsigned long r3 asm("3") = (unsigned long)(arg2) 84 #define CALL_ARGS_3(arg1, arg2, arg3) \ 85 CALL_ARGS_2(arg1, arg2); \ 86 register unsigned long r4 asm("4") = (unsigned long)(arg3) 87 #define CALL_ARGS_4(arg1, arg2, arg3, arg4) \ 88 CALL_ARGS_3(arg1, arg2, arg3); \ 89 register unsigned long r4 asm("5") = (unsigned long)(arg4) 90 #define CALL_ARGS_5(arg1, arg2, arg3, arg4, arg5) \ 91 CALL_ARGS_4(arg1, arg2, arg3, arg4); \ 92 register unsigned long r4 asm("6") = (unsigned long)(arg5) 93 94 #define CALL_FMT_0 "=&d" (r2) : 95 #define CALL_FMT_1 "+&d" (r2) : 96 #define CALL_FMT_2 CALL_FMT_1 "d" (r3), 97 #define CALL_FMT_3 CALL_FMT_2 "d" (r4), 98 #define CALL_FMT_4 CALL_FMT_3 "d" (r5), 99 #define CALL_FMT_5 CALL_FMT_4 "d" (r6), 100 101 #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory" 102 #define CALL_CLOBBER_4 CALL_CLOBBER_5 103 #define CALL_CLOBBER_3 CALL_CLOBBER_4, "5" 104 #define CALL_CLOBBER_2 CALL_CLOBBER_3, "4" 105 #define CALL_CLOBBER_1 CALL_CLOBBER_2, "3" 106 #define CALL_CLOBBER_0 CALL_CLOBBER_1 107 108 #define CALL_ON_STACK(fn, stack, nr, args...) \ 109 ({ \ 110 unsigned long frame = current_frame_address(); \ 111 CALL_ARGS_##nr(args); \ 112 unsigned long prev; \ 113 \ 114 asm volatile( \ 115 " la %[_prev],0(15)\n" \ 116 " lg 15,%[_stack]\n" \ 117 " stg %[_frame],%[_bc](15)\n" \ 118 " brasl 14,%[_fn]\n" \ 119 " la 15,0(%[_prev])\n" \ 120 : [_prev] "=&a" (prev), CALL_FMT_##nr \ 121 [_stack] "R" (stack), \ 122 [_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 123 [_frame] "d" (frame), \ 124 [_fn] "X" (fn) : CALL_CLOBBER_##nr); \ 125 r2; \ 126 }) 127 128 #define CALL_ON_STACK_NORETURN(fn, stack) \ 129 ({ \ 130 asm volatile( \ 131 " la 15,0(%[_stack])\n" \ 132 " xc %[_bc](8,15),%[_bc](15)\n" \ 133 " brasl 14,%[_fn]\n" \ 134 ::[_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 135 [_stack] "a" (stack), [_fn] "X" (fn)); \ 136 BUG(); \ 137 }) 138 139 #endif /* _ASM_S390_STACKTRACE_H */ 140