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 9enum stack_type { 10 STACK_TYPE_UNKNOWN, 11 STACK_TYPE_TASK, 12 STACK_TYPE_IRQ, 13 STACK_TYPE_NODAT, 14 STACK_TYPE_RESTART, 15}; 16 17struct stack_info { 18 enum stack_type type; 19 unsigned long begin, end; 20}; 21 22const char *stack_type_name(enum stack_type type); 23int get_stack_info(unsigned long sp, struct task_struct *task, 24 struct stack_info *info, unsigned long *visit_mask); 25 26static 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 36static __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 50struct 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 57struct 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/* 94 * To keep this simple mark register 2-6 as being changed (volatile) 95 * by the called function, even though register 6 is saved/nonvolatile. 96 */ 97#define CALL_FMT_0 "=&d" (r2) 98#define CALL_FMT_1 "+&d" (r2) 99#define CALL_FMT_2 CALL_FMT_1, "+&d" (r3) 100#define CALL_FMT_3 CALL_FMT_2, "+&d" (r4) 101#define CALL_FMT_4 CALL_FMT_3, "+&d" (r5) 102#define CALL_FMT_5 CALL_FMT_4, "+&d" (r6) 103 104#define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory" 105#define CALL_CLOBBER_4 CALL_CLOBBER_5 106#define CALL_CLOBBER_3 CALL_CLOBBER_4, "5" 107#define CALL_CLOBBER_2 CALL_CLOBBER_3, "4" 108#define CALL_CLOBBER_1 CALL_CLOBBER_2, "3" 109#define CALL_CLOBBER_0 CALL_CLOBBER_1 110 111#define CALL_ON_STACK(fn, stack, nr, args...) \ 112({ \ 113 unsigned long frame = current_frame_address(); \ 114 CALL_ARGS_##nr(args); \ 115 unsigned long prev; \ 116 \ 117 asm volatile( \ 118 " la %[_prev],0(15)\n" \ 119 " lg 15,%[_stack]\n" \ 120 " stg %[_frame],%[_bc](15)\n" \ 121 " brasl 14,%[_fn]\n" \ 122 " la 15,0(%[_prev])\n" \ 123 : [_prev] "=&a" (prev), CALL_FMT_##nr \ 124 : [_stack] "R" (stack), \ 125 [_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 126 [_frame] "d" (frame), \ 127 [_fn] "X" (fn) : CALL_CLOBBER_##nr); \ 128 r2; \ 129}) 130 131#define CALL_LARGS_0(...) \ 132 long dummy = 0 133#define CALL_LARGS_1(t1, a1) \ 134 long arg1 = (long)(t1)(a1) 135#define CALL_LARGS_2(t1, a1, t2, a2) \ 136 CALL_LARGS_1(t1, a1); \ 137 long arg2 = (long)(t2)(a2) 138#define CALL_LARGS_3(t1, a1, t2, a2, t3, a3) \ 139 CALL_LARGS_2(t1, a1, t2, a2); \ 140 long arg3 = (long)(t3)(a3) 141#define CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4) \ 142 CALL_LARGS_3(t1, a1, t2, a2, t3, a3); \ 143 long arg4 = (long)(t4)(a4) 144#define CALL_LARGS_5(t1, a1, t2, a2, t3, a3, t4, a4, t5, a5) \ 145 CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4); \ 146 long arg5 = (long)(t5)(a5) 147 148#define CALL_REGS_0 \ 149 register long r2 asm("2") = dummy 150#define CALL_REGS_1 \ 151 register long r2 asm("2") = arg1 152#define CALL_REGS_2 \ 153 CALL_REGS_1; \ 154 register long r3 asm("3") = arg2 155#define CALL_REGS_3 \ 156 CALL_REGS_2; \ 157 register long r4 asm("4") = arg3 158#define CALL_REGS_4 \ 159 CALL_REGS_3; \ 160 register long r5 asm("5") = arg4 161#define CALL_REGS_5 \ 162 CALL_REGS_4; \ 163 register long r6 asm("6") = arg5 164 165#define CALL_TYPECHECK_0(...) 166#define CALL_TYPECHECK_1(t, a, ...) \ 167 typecheck(t, a) 168#define CALL_TYPECHECK_2(t, a, ...) \ 169 CALL_TYPECHECK_1(__VA_ARGS__); \ 170 typecheck(t, a) 171#define CALL_TYPECHECK_3(t, a, ...) \ 172 CALL_TYPECHECK_2(__VA_ARGS__); \ 173 typecheck(t, a) 174#define CALL_TYPECHECK_4(t, a, ...) \ 175 CALL_TYPECHECK_3(__VA_ARGS__); \ 176 typecheck(t, a) 177#define CALL_TYPECHECK_5(t, a, ...) \ 178 CALL_TYPECHECK_4(__VA_ARGS__); \ 179 typecheck(t, a) 180 181#define CALL_PARM_0(...) void 182#define CALL_PARM_1(t, a, ...) t 183#define CALL_PARM_2(t, a, ...) t, CALL_PARM_1(__VA_ARGS__) 184#define CALL_PARM_3(t, a, ...) t, CALL_PARM_2(__VA_ARGS__) 185#define CALL_PARM_4(t, a, ...) t, CALL_PARM_3(__VA_ARGS__) 186#define CALL_PARM_5(t, a, ...) t, CALL_PARM_4(__VA_ARGS__) 187#define CALL_PARM_6(t, a, ...) t, CALL_PARM_5(__VA_ARGS__) 188 189/* 190 * Use call_on_stack() to call a function switching to a specified 191 * stack. Proper sign and zero extension of function arguments is 192 * done. Usage: 193 * 194 * rc = call_on_stack(nr, stack, rettype, fn, t1, a1, t2, a2, ...) 195 * 196 * - nr specifies the number of function arguments of fn. 197 * - stack specifies the stack to be used. 198 * - fn is the function to be called. 199 * - rettype is the return type of fn. 200 * - t1, a1, ... are pairs, where t1 must match the type of the first 201 * argument of fn, t2 the second, etc. a1 is the corresponding 202 * first function argument (not name), etc. 203 */ 204#define call_on_stack(nr, stack, rettype, fn, ...) \ 205({ \ 206 rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = fn; \ 207 unsigned long frame = current_frame_address(); \ 208 unsigned long __stack = stack; \ 209 unsigned long prev; \ 210 CALL_LARGS_##nr(__VA_ARGS__); \ 211 CALL_REGS_##nr; \ 212 \ 213 CALL_TYPECHECK_##nr(__VA_ARGS__); \ 214 asm volatile( \ 215 " lgr %[_prev],15\n" \ 216 " lg 15,%[_stack]\n" \ 217 " stg %[_frame],%[_bc](15)\n" \ 218 " brasl 14,%[_fn]\n" \ 219 " lgr 15,%[_prev]\n" \ 220 : [_prev] "=&d" (prev), CALL_FMT_##nr \ 221 : [_stack] "R" (__stack), \ 222 [_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 223 [_frame] "d" (frame), \ 224 [_fn] "X" (__fn) : CALL_CLOBBER_##nr); \ 225 (rettype)r2; \ 226}) 227 228#define CALL_ON_STACK_NORETURN(fn, stack) \ 229({ \ 230 asm volatile( \ 231 " la 15,0(%[_stack])\n" \ 232 " xc %[_bc](8,15),%[_bc](15)\n" \ 233 " brasl 14,%[_fn]\n" \ 234 ::[_bc] "i" (offsetof(struct stack_frame, back_chain)), \ 235 [_stack] "a" (stack), [_fn] "X" (fn)); \ 236 BUG(); \ 237}) 238 239#endif /* _ASM_S390_STACKTRACE_H */ 240