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/*
** S390 specific part of trace.c
**
** Other routines are in ../trace.c and need to be combined
** at link time with this code.
**
** Copyright (C) 2001,2005 IBM Corp.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <errno.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <asm/ptrace.h>
#include "ltrace.h"
#if (!defined(PTRACE_PEEKUSER) && defined(PTRACE_PEEKUSR))
# define PTRACE_PEEKUSER PTRACE_PEEKUSR
#endif
#if (!defined(PTRACE_POKEUSER) && defined(PTRACE_POKEUSR))
# define PTRACE_POKEUSER PTRACE_POKEUSR
#endif
void get_arch_dep(struct process *proc)
{
#ifdef __s390x__
unsigned long psw;
if (proc->arch_ptr)
return;
psw = ptrace(PTRACE_PEEKUSER, proc->pid, PT_PSWMASK, 0);
if ((psw & 0x000000180000000) == 0x000000080000000) {
proc->mask_32bit = 1;
proc->personality = 1;
}
proc->arch_ptr = (void *)1;
#endif
}
/* Returns 1 if syscall, 2 if sysret, 0 otherwise.
*/
int syscall_p(struct process *proc, int status, int *sysnum)
{
long pc, opcode, offset_reg, scno, tmp;
void *svc_addr;
int gpr_offset[16] = { PT_GPR0, PT_GPR1, PT_ORIGGPR2, PT_GPR3,
PT_GPR4, PT_GPR5, PT_GPR6, PT_GPR7,
PT_GPR8, PT_GPR9, PT_GPR10, PT_GPR11,
PT_GPR12, PT_GPR13, PT_GPR14, PT_GPR15
};
if (WIFSTOPPED(status)
&& WSTOPSIG(status) == (SIGTRAP | proc->tracesysgood)) {
/*
* If we have PTRACE_O_TRACESYSGOOD and we have the new style
* of passing the system call number to user space via PT_GPR2
* then the task is quite easy.
*/
*sysnum = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR2, 0);
if (proc->tracesysgood) {
/* System call was encountered... */
if (proc->callstack_depth > 0 &&
proc->callstack[proc->callstack_depth -
1].is_syscall) {
/* syscall exit */
*sysnum =
proc->callstack[proc->callstack_depth -
1].c_un.syscall;
return 2;
} else {
/* syscall enter */
if (*sysnum != -ENOSYS)
return 1;
}
}
/*
* At least one of the two requirements mentioned above is not
* met. Therefore the fun part starts here:
* We try to do some instruction decoding without even knowing
* the instruction code length of the last instruction executed.
* Needs to be done to get the system call number or to decide
* if we reached a breakpoint or even checking for a completely
* unrelated instruction.
* Just a heuristic that most of the time appears to work...
*/
pc = ptrace(PTRACE_PEEKUSER, proc->pid, PT_PSWADDR, 0);
opcode = ptrace(PTRACE_PEEKTEXT, proc->pid,
(char *)(pc - sizeof(long)), 0);
if ((opcode & 0xffff) == 0x0001) {
/* Breakpoint */
return 0;
} else if ((opcode & 0xff00) == 0x0a00) {
/* SVC opcode */
scno = opcode & 0xff;
} else if ((opcode & 0xff000000) == 0x44000000) {
/* Instruction decoding of EXECUTE... */
svc_addr = (void *)(opcode & 0xfff);
offset_reg = (opcode & 0x000f0000) >> 16;
if (offset_reg)
svc_addr += ptrace(PTRACE_PEEKUSER, proc->pid,
gpr_offset[offset_reg], 0);
offset_reg = (opcode & 0x0000f000) >> 12;
if (offset_reg)
svc_addr += ptrace(PTRACE_PEEKUSER, proc->pid,
gpr_offset[offset_reg], 0);
scno = ptrace(PTRACE_PEEKTEXT, proc->pid, svc_addr, 0);
#ifdef __s390x__
scno >>= 48;
#else
scno >>= 16;
#endif
if ((scno & 0xff00) != 0x0a000)
return 0;
tmp = 0;
offset_reg = (opcode & 0x00f00000) >> 20;
if (offset_reg)
tmp = ptrace(PTRACE_PEEKUSER, proc->pid,
gpr_offset[offset_reg], 0);
scno = (scno | tmp) & 0xff;
} else {
/* No opcode related to syscall handling */
return 0;
}
if (scno == 0)
scno = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR1, 0);
*sysnum = scno;
/* System call was encountered... */
if (proc->callstack_depth > 0 &&
proc->callstack[proc->callstack_depth - 1].is_syscall) {
return 2;
} else {
return 1;
}
}
/* Unknown status... */
return 0;
}
long gimme_arg(enum tof type, struct process *proc, arg_type_info *info)
{
int arg_num = info->arg_num;
long ret;
switch (arg_num) {
case -1: /* return value */
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR2, 0);
break;
case 0:
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_ORIGGPR2, 0);
break;
case 1:
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR3, 0);
break;
case 2:
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR4, 0);
break;
case 3:
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR5, 0);
break;
case 4:
ret = ptrace(PTRACE_PEEKUSER, proc->pid, PT_GPR6, 0);
break;
default:
fprintf(stderr, "gimme_arg called with wrong arguments\n");
exit(2);
}
#ifdef __s390x__
if (proc->mask_32bit)
ret &= 0xffffffff;
#endif
return ret;
}
void save_register_args(enum tof type, struct process *proc)
{
}
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