/* 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> 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; } 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_stack_pointer(); return (unsigned long) task->thread.ksp; } /* * Stack layout of a C stack frame. */ #ifndef __PACK_STACK struct stack_frame { unsigned long back_chain; unsigned long empty1[5]; unsigned long gprs[10]; unsigned int empty2[8]; }; #else struct stack_frame { unsigned long empty1[5]; unsigned int empty2[8]; unsigned long gprs[10]; unsigned long back_chain; }; #endif /* * Unlike current_stack_pointer() which simply returns 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)) /* * 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; \ }) #define call_on_stack_noreturn(fn, stack) \ ({ \ void (*__fn)(void) = fn; \ \ asm volatile( \ " la 15,0(%[_stack])\n" \ " xc %[_bc](8,15),%[_bc](15)\n" \ " brasl 14,%[_fn]\n" \ ::[_bc] "i" (offsetof(struct stack_frame, back_chain)), \ [_stack] "a" (stack), [_fn] "X" (__fn)); \ BUG(); \ }) #endif /* _ASM_S390_STACKTRACE_H */