| 1 | /* |
| 2 | * arch/ubicom32/mm/fault.c |
| 3 | * Ubicom32 architecture page fault implementation. |
| 4 | * |
| 5 | * (C) Copyright 2009, Ubicom, Inc. |
| 6 | * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, |
| 7 | * Copyright (C) 2000 Lineo, Inc. (www.lineo.com) |
| 8 | * |
| 9 | * Based on: |
| 10 | * |
| 11 | * linux/arch/m68k/mm/fault.c |
| 12 | * |
| 13 | * Copyright (C) 1995 Hamish Macdonald |
| 14 | * |
| 15 | * This file is part of the Ubicom32 Linux Kernel Port. |
| 16 | * |
| 17 | * The Ubicom32 Linux Kernel Port is free software: you can redistribute |
| 18 | * it and/or modify it under the terms of the GNU General Public License |
| 19 | * as published by the Free Software Foundation, either version 2 of the |
| 20 | * License, or (at your option) any later version. |
| 21 | * |
| 22 | * The Ubicom32 Linux Kernel Port is distributed in the hope that it |
| 23 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 24 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 25 | * the GNU General Public License for more details. |
| 26 | * |
| 27 | * You should have received a copy of the GNU General Public License |
| 28 | * along with the Ubicom32 Linux Kernel Port. If not, |
| 29 | * see <http://www.gnu.org/licenses/>. |
| 30 | * |
| 31 | * Ubicom32 implementation derived from (with many thanks): |
| 32 | * arch/m68knommu |
| 33 | * arch/blackfin |
| 34 | * arch/parisc |
| 35 | */ |
| 36 | |
| 37 | #include <linux/module.h> |
| 38 | #include <linux/mman.h> |
| 39 | #include <linux/mm.h> |
| 40 | #include <linux/kernel.h> |
| 41 | #include <linux/ptrace.h> |
| 42 | |
| 43 | #include <asm/system.h> |
| 44 | #include <asm/pgtable.h> |
| 45 | |
| 46 | extern void die_if_kernel(char *, struct pt_regs *, long); |
| 47 | |
| 48 | /* |
| 49 | * This routine handles page faults. It determines the problem, and |
| 50 | * then passes it off to one of the appropriate routines. |
| 51 | * |
| 52 | * error_code: |
| 53 | * bit 0 == 0 means no page found, 1 means protection fault |
| 54 | * bit 1 == 0 means read, 1 means write |
| 55 | * |
| 56 | * If this routine detects a bad access, it returns 1, otherwise it |
| 57 | * returns 0. |
| 58 | */ |
| 59 | asmlinkage int do_page_fault(struct pt_regs *regs, unsigned long address, |
| 60 | unsigned long error_code) |
| 61 | { |
| 62 | #ifdef DEBUG |
| 63 | printk (KERN_DEBUG "regs->sr=%#x, regs->pc=%#lx, address=%#lx, %ld\n", |
| 64 | regs->sr, regs->pc, address, error_code); |
| 65 | #endif |
| 66 | |
| 67 | /* |
| 68 | * Oops. The kernel tried to access some bad page. We'll have to |
| 69 | * terminate things with extreme prejudice. |
| 70 | */ |
| 71 | if ((unsigned long) address < PAGE_SIZE) { |
| 72 | printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference"); |
| 73 | } else |
| 74 | printk(KERN_ALERT "Unable to handle kernel access"); |
| 75 | printk(KERN_ALERT " at virtual address %08lx\n",address); |
| 76 | die_if_kernel("Oops", regs, error_code); |
| 77 | do_exit(SIGKILL); |
| 78 | |
| 79 | return 1; |
| 80 | } |
| 81 | |
