| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_S390_STACKTRACE_H |
| #define _ASM_S390_STACKTRACE_H |
| |
| #include <linux/uaccess.h> |
| #include <linux/ptrace.h> |
| #include <asm/switch_to.h> |
| |
| struct stack_frame_user { |
| unsigned long back_chain; |
| unsigned long empty1[5]; |
| unsigned long gprs[10]; |
| unsigned long empty2[4]; |
| }; |
| |
| enum stack_type { |
| STACK_TYPE_UNKNOWN, |
| STACK_TYPE_TASK, |
| STACK_TYPE_IRQ, |
| STACK_TYPE_NODAT, |
| STACK_TYPE_RESTART, |
| STACK_TYPE_MCCK, |
| }; |
| |
| struct stack_info { |
| enum stack_type type; |
| unsigned long begin, end; |
| }; |
| |
| const char *stack_type_name(enum stack_type type); |
| int get_stack_info(unsigned long sp, struct task_struct *task, |
| struct stack_info *info, unsigned long *visit_mask); |
| |
| static inline bool on_stack(struct stack_info *info, |
| unsigned long addr, size_t len) |
| { |
| if (info->type == STACK_TYPE_UNKNOWN) |
| return false; |
| if (addr + len < addr) |
| return false; |
| return addr >= info->begin && addr + len <= info->end; |
| } |
| |
| /* |
| * Stack layout of a C stack frame. |
| * Kernel uses the packed stack layout (-mpacked-stack). |
| */ |
| struct stack_frame { |
| union { |
| unsigned long empty[9]; |
| struct { |
| unsigned long sie_control_block; |
| unsigned long sie_savearea; |
| unsigned long sie_reason; |
| unsigned long sie_flags; |
| unsigned long sie_control_block_phys; |
| }; |
| }; |
| unsigned long gprs[10]; |
| unsigned long back_chain; |
| }; |
| |
| /* |
| * Unlike current_stack_pointer which simply contains the current value of %r15 |
| * current_frame_address() returns function stack frame address, which matches |
| * %r15 upon function invocation. It may differ from %r15 later if function |
| * allocates stack for local variables or new stack frame to call other |
| * functions. |
| */ |
| #define current_frame_address() \ |
| ((unsigned long)__builtin_frame_address(0) - \ |
| offsetof(struct stack_frame, back_chain)) |
| |
| static __always_inline unsigned long get_stack_pointer(struct task_struct *task, |
| struct pt_regs *regs) |
| { |
| if (regs) |
| return (unsigned long)kernel_stack_pointer(regs); |
| if (task == current) |
| return current_frame_address(); |
| return (unsigned long)task->thread.ksp; |
| } |
| |
| /* |
| * To keep this simple mark register 2-6 as being changed (volatile) |
| * by the called function, even though register 6 is saved/nonvolatile. |
| */ |
| #define CALL_FMT_0 "=&d" (r2) |
| #define CALL_FMT_1 "+&d" (r2) |
| #define CALL_FMT_2 CALL_FMT_1, "+&d" (r3) |
| #define CALL_FMT_3 CALL_FMT_2, "+&d" (r4) |
| #define CALL_FMT_4 CALL_FMT_3, "+&d" (r5) |
| #define CALL_FMT_5 CALL_FMT_4, "+&d" (r6) |
| |
| #define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory" |
| #define CALL_CLOBBER_4 CALL_CLOBBER_5 |
| #define CALL_CLOBBER_3 CALL_CLOBBER_4, "5" |
| #define CALL_CLOBBER_2 CALL_CLOBBER_3, "4" |
| #define CALL_CLOBBER_1 CALL_CLOBBER_2, "3" |
| #define CALL_CLOBBER_0 CALL_CLOBBER_1 |
| |
| #define CALL_LARGS_0(...) \ |
| long dummy = 0 |
| #define CALL_LARGS_1(t1, a1) \ |
| long arg1 = (long)(t1)(a1) |
| #define CALL_LARGS_2(t1, a1, t2, a2) \ |
| CALL_LARGS_1(t1, a1); \ |
| long arg2 = (long)(t2)(a2) |
| #define CALL_LARGS_3(t1, a1, t2, a2, t3, a3) \ |
| CALL_LARGS_2(t1, a1, t2, a2); \ |
| long arg3 = (long)(t3)(a3) |
| #define CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4) \ |
| CALL_LARGS_3(t1, a1, t2, a2, t3, a3); \ |
| long arg4 = (long)(t4)(a4) |
| #define CALL_LARGS_5(t1, a1, t2, a2, t3, a3, t4, a4, t5, a5) \ |
| CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4); \ |
| long arg5 = (long)(t5)(a5) |
| |
| #define CALL_REGS_0 \ |
| register long r2 asm("2") = dummy |
| #define CALL_REGS_1 \ |
| register long r2 asm("2") = arg1 |
| #define CALL_REGS_2 \ |
| CALL_REGS_1; \ |
| register long r3 asm("3") = arg2 |
| #define CALL_REGS_3 \ |
| CALL_REGS_2; \ |
| register long r4 asm("4") = arg3 |
| #define CALL_REGS_4 \ |
| CALL_REGS_3; \ |
| register long r5 asm("5") = arg4 |
| #define CALL_REGS_5 \ |
| CALL_REGS_4; \ |
| register long r6 asm("6") = arg5 |
| |
| #define CALL_TYPECHECK_0(...) |
| #define CALL_TYPECHECK_1(t, a, ...) \ |
| typecheck(t, a) |
| #define CALL_TYPECHECK_2(t, a, ...) \ |
| CALL_TYPECHECK_1(__VA_ARGS__); \ |
| typecheck(t, a) |
| #define CALL_TYPECHECK_3(t, a, ...) \ |
| CALL_TYPECHECK_2(__VA_ARGS__); \ |
| typecheck(t, a) |
| #define CALL_TYPECHECK_4(t, a, ...) \ |
| CALL_TYPECHECK_3(__VA_ARGS__); \ |
| typecheck(t, a) |
| #define CALL_TYPECHECK_5(t, a, ...) \ |
| CALL_TYPECHECK_4(__VA_ARGS__); \ |
| typecheck(t, a) |
| |
| #define CALL_PARM_0(...) void |
| #define CALL_PARM_1(t, a, ...) t |
| #define CALL_PARM_2(t, a, ...) t, CALL_PARM_1(__VA_ARGS__) |
| #define CALL_PARM_3(t, a, ...) t, CALL_PARM_2(__VA_ARGS__) |
| #define CALL_PARM_4(t, a, ...) t, CALL_PARM_3(__VA_ARGS__) |
| #define CALL_PARM_5(t, a, ...) t, CALL_PARM_4(__VA_ARGS__) |
| #define CALL_PARM_6(t, a, ...) t, CALL_PARM_5(__VA_ARGS__) |
| |
| /* |
| * Use call_on_stack() to call a function switching to a specified |
| * stack. Proper sign and zero extension of function arguments is |
| * done. Usage: |
| * |
| * rc = call_on_stack(nr, stack, rettype, fn, t1, a1, t2, a2, ...) |
| * |
| * - nr specifies the number of function arguments of fn. |
| * - stack specifies the stack to be used. |
| * - fn is the function to be called. |
| * - rettype is the return type of fn. |
| * - t1, a1, ... are pairs, where t1 must match the type of the first |
| * argument of fn, t2 the second, etc. a1 is the corresponding |
| * first function argument (not name), etc. |
| */ |
| #define call_on_stack(nr, stack, rettype, fn, ...) \ |
| ({ \ |
| rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = fn; \ |
| unsigned long frame = current_frame_address(); \ |
| unsigned long __stack = stack; \ |
| unsigned long prev; \ |
| CALL_LARGS_##nr(__VA_ARGS__); \ |
| CALL_REGS_##nr; \ |
| \ |
| CALL_TYPECHECK_##nr(__VA_ARGS__); \ |
| asm volatile( \ |
| " lgr %[_prev],15\n" \ |
| " lg 15,%[_stack]\n" \ |
| " stg %[_frame],%[_bc](15)\n" \ |
| " brasl 14,%[_fn]\n" \ |
| " lgr 15,%[_prev]\n" \ |
| : [_prev] "=&d" (prev), CALL_FMT_##nr \ |
| : [_stack] "R" (__stack), \ |
| [_bc] "i" (offsetof(struct stack_frame, back_chain)), \ |
| [_frame] "d" (frame), \ |
| [_fn] "X" (__fn) : CALL_CLOBBER_##nr); \ |
| (rettype)r2; \ |
| }) |
| |
| /* |
| * Use call_nodat() to call a function with DAT disabled. |
| * Proper sign and zero extension of function arguments is done. |
| * Usage: |
| * |
| * rc = call_nodat(nr, rettype, fn, t1, a1, t2, a2, ...) |
| * |
| * - nr specifies the number of function arguments of fn. |
| * - fn is the function to be called, where fn is a physical address. |
| * - rettype is the return type of fn. |
| * - t1, a1, ... are pairs, where t1 must match the type of the first |
| * argument of fn, t2 the second, etc. a1 is the corresponding |
| * first function argument (not name), etc. |
| * |
| * fn() is called with standard C function call ABI, with the exception |
| * that no useful stackframe or stackpointer is passed via register 15. |
| * Therefore the called function must not use r15 to access the stack. |
| */ |
| #define call_nodat(nr, rettype, fn, ...) \ |
| ({ \ |
| rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = (fn); \ |
| /* aligned since psw_leave must not cross page boundary */ \ |
| psw_t __aligned(16) psw_leave; \ |
| psw_t psw_enter; \ |
| CALL_LARGS_##nr(__VA_ARGS__); \ |
| CALL_REGS_##nr; \ |
| \ |
| CALL_TYPECHECK_##nr(__VA_ARGS__); \ |
| psw_enter.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT; \ |
| psw_enter.addr = (unsigned long)__fn; \ |
| asm volatile( \ |
| " epsw 0,1\n" \ |
| " risbg 1,0,0,31,32\n" \ |
| " larl 7,1f\n" \ |
| " stg 1,%[psw_leave]\n" \ |
| " stg 7,8+%[psw_leave]\n" \ |
| " la 7,%[psw_leave]\n" \ |
| " lra 7,0(7)\n" \ |
| " larl 1,0f\n" \ |
| " lra 14,0(1)\n" \ |
| " lpswe %[psw_enter]\n" \ |
| "0: lpswe 0(7)\n" \ |
| "1:\n" \ |
| : CALL_FMT_##nr, [psw_leave] "=Q" (psw_leave) \ |
| : [psw_enter] "Q" (psw_enter) \ |
| : "7", CALL_CLOBBER_##nr); \ |
| (rettype)r2; \ |
| }) |
| |
| #endif /* _ASM_S390_STACKTRACE_H */ |