arch/um/os-Linux/skas/trap.c

   1 /*
   2  * Copyright (C) 2002 - 2003 Jeff Dike (jdike@addtoit.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <signal.h>
   7 #include <errno.h>
   8 #include "kern_util.h"
   9 #include "as-layout.h"
  10 #include "task.h"
  11 #include "sigcontext.h"
  12 #include "skas.h"
  13 #include "ptrace_user.h"
  14 #include "sysdep/ptrace.h"
  15 #include "sysdep/ptrace_user.h"
  16 #include "os.h"
  17
  18 void sig_handler_common_skas(int sig, void *sc_ptr)
  19 {
  20         struct sigcontext *sc = sc_ptr;
  21         union uml_pt_regs *r;
  22         void (*handler)(int, union uml_pt_regs *);
  23         int save_user, save_errno = errno;
  24
  25         /* This is done because to allow SIGSEGV to be delivered inside a SEGV
  26          * handler.  This can happen in copy_user, and if SEGV is disabled,
  27          * the process will die.
  28          * XXX Figure out why this is better than SA_NODEFER
  29          */
  30         if(sig == SIGSEGV)
  31                 change_sig(SIGSEGV, 1);
  32
  33         r = TASK_REGS(get_current());
  34         save_user = r->skas.is_user;
  35         r->skas.is_user = 0;
  36         if ( sig == SIGFPE || sig == SIGSEGV ||
  37              sig == SIGBUS || sig == SIGILL ||
  38              sig == SIGTRAP ) {
  39                 GET_FAULTINFO_FROM_SC(r->skas.faultinfo, sc);
  40         }
  41
  42         change_sig(SIGUSR1, 1);
  43
  44         handler = sig_info[sig];
  45
  46         /* unblock SIGALRM, SIGVTALRM, SIGIO if sig isn't IRQ signal */
  47         if (sig != SIGIO && sig != SIGWINCH &&
  48             sig != SIGVTALRM && sig != SIGALRM)
  49                 unblock_signals();
  50
  51         handler(sig, r);
  52
  53         errno = save_errno;
  54         r->skas.is_user = save_user;
  55 }
  56
  57 extern int ptrace_faultinfo;
  58
  59 void user_signal(int sig, union uml_pt_regs *regs, int pid)
  60 {
  61         void (*handler)(int, union uml_pt_regs *);
  62         int segv = ((sig == SIGFPE) || (sig == SIGSEGV) || (sig == SIGBUS) ||
  63                     (sig == SIGILL) || (sig == SIGTRAP));
  64
  65         if (segv)
  66                 get_skas_faultinfo(pid, &regs->skas.faultinfo);
  67
  68         handler = sig_info[sig];
  69         handler(sig, (union uml_pt_regs *) regs);
  70
  71         unblock_signals();
  72 }