arch/sh/mm/fault-nommu.c

   1 /*
   2  * arch/sh/mm/fault-nommu.c
   3  *
   4  * Copyright (C) 2002 Paul Mundt
   5  *
   6  * Based on linux/arch/sh/mm/fault.c:
   7  *  Copyright (C) 1999  Niibe Yutaka
   8  *
   9  * Released under the terms of the GNU GPL v2.0.
  10  */
  11
  12 #include <linux/signal.h>
  13 #include <linux/sched.h>
  14 #include <linux/kernel.h>
  15 #include <linux/errno.h>
  16 #include <linux/string.h>
  17 #include <linux/types.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/mman.h>
  20 #include <linux/mm.h>
  21 #include <linux/smp.h>
  22 #include <linux/smp_lock.h>
  23 #include <linux/interrupt.h>
  24
  25 #include <asm/system.h>
  26 #include <asm/io.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/pgalloc.h>
  29 #include <asm/mmu_context.h>
  30 #include <asm/cacheflush.h>
  31
  32 #if defined(CONFIG_SH_KGDB)
  33 #include <asm/kgdb.h>
  34 #endif
  35
  36 extern void die(const char *,struct pt_regs *,long);
  37
  38 /*
  39  * This routine handles page faults.  It determines the address,
  40  * and the problem, and then passes it off to one of the appropriate
  41  * routines.
  42  */
  43 asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  44                               unsigned long address)
  45 {
  46 #if defined(CONFIG_SH_KGDB)
  47         if (kgdb_nofault && kgdb_bus_err_hook)
  48                 kgdb_bus_err_hook();
  49 #endif
  50
  51         /*
  52          * Oops. The kernel tried to access some bad page. We'll have to
  53          * terminate things with extreme prejudice.
  54          *
  55          */
  56         if (address < PAGE_SIZE) {
  57                 printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
  58         } else {
  59                 printk(KERN_ALERT "Unable to handle kernel paging request");
  60         }
  61
  62         printk(" at virtual address %08lx\n", address);
  63         printk(KERN_ALERT "pc = %08lx\n", regs->pc);
  64
  65         die("Oops", regs, writeaccess);
  66         do_exit(SIGKILL);
  67 }
  68
  69 asmlinkage int __do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  70                                unsigned long address)
  71 {
  72 #if defined(CONFIG_SH_KGDB)
  73         if (kgdb_nofault && kgdb_bus_err_hook)
  74                 kgdb_bus_err_hook();
  75 #endif
  76
  77         if (address >= TASK_SIZE)
  78                 return 1;
  79
  80         return 0;
  81 }
  82