vserver 1.9.5.x5

[linux-2.6.git] / arch / m32r / mm / fault.c

diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c
index 393ff03..bf7fb58 100644 (file)
--- a/arch/m32r/mm/fault.c
+++ b/arch/m32r/mm/fault.c
@@ -2,13 +2,12 @@
  *  linux/arch/m32r/mm/fault.c
  *
  *  Copyright (c) 2001, 2002  Hitoshi Yamamoto, and H. Kondo
+ *  Copyright (c) 2004  Naoto Sugai, NIIBE Yutaka
  *
  *  Some code taken from i386 version.
  *    Copyright (C) 1995  Linus Torvalds
  */
 
-/* $Id$ */
-
 #include <linux/config.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
@@ -96,6 +95,11 @@ void bust_spinlocks(int yes)
  *  bit 2 == 0 means kernel, 1 means user-mode
  *  bit 3 == 0 means data, 1 means instruction
  *======================================================================*/
+#define ACE_PROTECTION         1
+#define ACE_WRITE              2
+#define ACE_USERMODE           4
+#define ACE_INSTRUCTION                8
+
 asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
   unsigned long address)
 {
@@ -126,10 +130,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
         * nothing more.
         *
         * This verifies that the fault happens in kernel space
-        * (error_code & 4) == 0, and that the fault was not a
-        * protection error (error_code & 1) == 0.
+        * (error_code & ACE_USERMODE) == 0, and that the fault was not a
+        * protection error (error_code & ACE_PROTECTION) == 0.
         */
-       if (address >= TASK_SIZE && !(error_code & 4))
+       if (address >= TASK_SIZE && !(error_code & ACE_USERMODE))
                goto vmalloc_fault;
 
        mm = tsk->mm;
@@ -157,7 +161,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
         * thus avoiding the deadlock.
         */
        if (!down_read_trylock(&mm->mmap_sem)) {
-               if ((error_code & 4) == 0 &&
+               if ((error_code & ACE_USERMODE) == 0 &&
                    !search_exception_tables(regs->psw))
                        goto bad_area_nosemaphore;
                down_read(&mm->mmap_sem);
@@ -171,7 +175,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
        if (!(vma->vm_flags & VM_GROWSDOWN))
                goto bad_area;
 #if 0
-       if (error_code & 4) {
+       if (error_code & ACE_USERMODE) {
                /*
                 * accessing the stack below "spu" is always a bug.
                 * The "+ 4" is there due to the push instruction
@@ -191,27 +195,34 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
 good_area:
        info.si_code = SEGV_ACCERR;
        write = 0;
-       switch (error_code & 3) {
+       switch (error_code & (ACE_WRITE|ACE_PROTECTION)) {
                default:        /* 3: write, present */
                        /* fall through */
-               case 2:         /* write, not present */
+               case ACE_WRITE: /* write, not present */
                        if (!(vma->vm_flags & VM_WRITE))
                                goto bad_area;
                        write++;
                        break;
-               case 1:         /* read, present */
+               case ACE_PROTECTION:    /* read, present */
                case 0:         /* read, not present */
                        if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
                                goto bad_area;
        }
 
+       /*
+        * For instruction access exception, check if the area is executable
+        */
+       if ((error_code & ACE_INSTRUCTION) && !(vma->vm_flags & VM_EXEC))
+         goto bad_area;
+
 survive:
        /*
         * If for any reason at all we couldn't handle the fault,
         * make sure we exit gracefully rather than endlessly redo
         * the fault.
         */
-       addr = (address & PAGE_MASK) | (error_code & 8);
+       addr = (address & PAGE_MASK);
+       set_thread_fault_code(error_code);
        switch (handle_mm_fault(mm, vma, addr, write)) {
                case VM_FAULT_MINOR:
                        tsk->min_flt++;
@@ -226,7 +237,7 @@ survive:
                default:
                        BUG();
        }
-
+       set_thread_fault_code(0);
        up_read(&mm->mmap_sem);
        return;
 
@@ -239,7 +250,7 @@ bad_area:
 
 bad_area_nosemaphore:
        /* User mode accesses just cause a SIGSEGV */
-       if (error_code & 4) {
+       if (error_code & ACE_USERMODE) {
                tsk->thread.address = address;
                tsk->thread.error_code = error_code | (address >= TASK_SIZE);
                tsk->thread.trap_no = 14;
@@ -295,7 +306,7 @@ out_of_memory:
                goto survive;
        }
        printk("VM: killing process %s\n", tsk->comm);
-       if (error_code & 4)
+       if (error_code & ACE_USERMODE)
                do_exit(SIGKILL);
        goto no_context;
 
@@ -303,7 +314,7 @@ do_sigbus:
        up_read(&mm->mmap_sem);
 
        /* Kernel mode? Handle exception or die */
-       if (!(error_code & 4))
+       if (!(error_code & ACE_USERMODE))
                goto no_context;
 
        tsk->thread.address = address;
@@ -352,7 +363,7 @@ vmalloc_fault:
                if (!pte_present(*pte_k))
                        goto no_context;
 
-               addr = (address & PAGE_MASK) | (error_code & 8);
+               addr = (address & PAGE_MASK) | (error_code & ACE_INSTRUCTION);
                update_mmu_cache(NULL, addr, *pte_k);
                return;
        }
@@ -370,7 +381,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddr,
        unsigned long *entry1, *entry2;
        unsigned long pte_data, flags;
        unsigned int *entry_dat;
-       int inst = vaddr & 8;
+       int inst = get_thread_fault_code() & ACE_INSTRUCTION;
        int i;
 
        /* Ptrace may call this routine. */