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/interrupt.h>
  23
  24 #include <asm/system.h>
  25 #include <asm/io.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/pgalloc.h>
  28 #include <asm/mmu_context.h>
  29 #include <asm/cacheflush.h>
  30
  31 #if defined(CONFIG_SH_KGDB)
  32 #include <asm/kgdb.h>
  33 #endif
  34
  35 extern void die(const char *,struct pt_regs *,long);
  36
  37 /*
  38  * This routine handles page faults.  It determines the address,
  39  * and the problem, and then passes it off to one of the appropriate
  40  * routines.
  41  */
  42 asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  43                               unsigned long address)
  44 {
  45 #if defined(CONFIG_SH_KGDB)
  46         if (kgdb_nofault && kgdb_bus_err_hook)
  47                 kgdb_bus_err_hook();
  48 #endif
  49
  50         /*
  51          * Oops. The kernel tried to access some bad page. We'll have to
  52          * terminate things with extreme prejudice.
  53          *
  54          */
  55         if (address < PAGE_SIZE) {
  56                 printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
  57         } else {
  58                 printk(KERN_ALERT "Unable to handle kernel paging request");
  59         }
  60
  61         printk(" at virtual address %08lx\n", address);
  62         printk(KERN_ALERT "pc = %08lx\n", regs->pc);
  63
  64         die("Oops", regs, writeaccess);
  65         do_exit(SIGKILL);
  66 }
  67
  68 asmlinkage int __do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
  69                                unsigned long address)
  70 {
  71 #if defined(CONFIG_SH_KGDB)
  72         if (kgdb_nofault && kgdb_bus_err_hook)
  73                 kgdb_bus_err_hook();
  74 #endif
  75
  76         if (address >= TASK_SIZE)
  77                 return 1;
  78
  79         return 0;
  80 }
  81