arch/um/kernel/tt/trap_user.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <stdlib.h>
   7 #include <errno.h>
   8 #include <signal.h>
   9 #include <asm/sigcontext.h>
  10 #include "sysdep/ptrace.h"
  11 #include "signal_user.h"
  12 #include "user_util.h"
  13 #include "kern_util.h"
  14 #include "task.h"
  15 #include "tt.h"
  16
  17 void sig_handler_common_tt(int sig, void *sc_ptr)
  18 {
  19         struct sigcontext *sc = sc_ptr;
  20         struct tt_regs save_regs, *r;
  21         struct signal_info *info;
  22         int save_errno = errno, is_user;
  23
  24         unprotect_kernel_mem();
  25
  26         /* This is done because to allow SIGSEGV to be delivered inside a SEGV
  27          * handler.  This can happen in copy_user, and if SEGV is disabled,
  28          * the process will die.
  29          */
  30         if(sig == SIGSEGV)
  31                 change_sig(SIGSEGV, 1);
  32
  33         r = &TASK_REGS(get_current())->tt;
  34         save_regs = *r;
  35         is_user = user_context(SC_SP(sc));
  36         r->sc = sc;
  37         if(sig != SIGUSR2)
  38                 r->syscall = -1;
  39
  40         info = &sig_info[sig];
  41         if(!info->is_irq) unblock_signals();
  42
  43         (*info->handler)(sig, (union uml_pt_regs *) r);
  44
  45         if(is_user){
  46                 interrupt_end();
  47                 block_signals();
  48                 set_user_mode(NULL);
  49         }
  50         *r = save_regs;
  51         errno = save_errno;
  52         if(is_user) protect_kernel_mem();
  53 }
  54
  55 /*
  56  * Overrides for Emacs so that we follow Linus's tabbing style.
  57  * Emacs will notice this stuff at the end of the file and automatically
  58  * adjust the settings for this buffer only.  This must remain at the end
  59  * of the file.
  60  * ---------------------------------------------------------------------------
  61  * Local variables:
  62  * c-file-style: "linux"
  63  * End:
  64  */