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Diffstat (limited to 'arch/s390/include/asm/stacktrace.h')
| -rw-r--r-- | arch/s390/include/asm/stacktrace.h | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h new file mode 100644 index 0000000000..78f7b729b6 --- /dev/null +++ b/arch/s390/include/asm/stacktrace.h @@ -0,0 +1,241 @@ +/* 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; +} + +/* + * 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 */ |