arch/um/kernel/tt/syscall_user.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <unistd.h>
   7 #include <signal.h>
   8 #include <errno.h>
   9 #include <asm/unistd.h>
  10 #include "sysdep/ptrace.h"
  11 #include "sigcontext.h"
  12 #include "ptrace_user.h"
  13 #include "task.h"
  14 #include "kern_util.h"
  15 #include "syscall.h"
  16 #include "tt.h"
  17
  18 void do_sigtrap(void *task)
  19 {
  20         UPT_SYSCALL_NR(TASK_REGS(task)) = -1;
  21 }
  22
  23 void do_syscall(void *task, int pid, int local_using_sysemu)
  24 {
  25         unsigned long proc_regs[FRAME_SIZE];
  26
  27         if(ptrace_getregs(pid, proc_regs) < 0)
  28                 tracer_panic("Couldn't read registers");
  29
  30         UPT_SYSCALL_NR(TASK_REGS(task)) = PT_SYSCALL_NR(proc_regs);
  31
  32 #ifdef UPT_ORIGGPR2
  33         UPT_ORIGGPR2(TASK_REGS(task)) = REGS_ORIGGPR2(proc_regs);
  34 #endif
  35
  36         if(((unsigned long *) PT_IP(proc_regs) >= &_stext) &&
  37            ((unsigned long *) PT_IP(proc_regs) <= &_etext))
  38                 tracer_panic("I'm tracing myself and I can't get out");
  39
  40         /* advanced sysemu mode set syscall number to -1 automatically */
  41         if (local_using_sysemu==2)
  42                 return;
  43
  44         /* syscall number -1 in sysemu skips syscall restarting in host */
  45         if(ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
  46                   local_using_sysemu ? -1 : __NR_getpid) < 0)
  47                 tracer_panic("do_syscall : Nullifying syscall failed, "
  48                              "errno = %d", errno);
  49 }
  50
  51 /*
  52  * Overrides for Emacs so that we follow Linus's tabbing style.
  53  * Emacs will notice this stuff at the end of the file and automatically
  54  * adjust the settings for this buffer only.  This must remain at the end
  55  * of the file.
  56  * ---------------------------------------------------------------------------
  57  * Local variables:
  58  * c-file-style: "linux"
  59  * End:
  60  */