Merge branch 'release' of git://lm-sensors.org/kernel/mhoffman/hwmon-2.6

[sfrench/cifs-2.6.git] / arch / ia64 / mm / fault.c

diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index 21658e02116c5a77f3694f64ba15e3856d5938c8..9150ffaff9e891da5ed52fbc05ed040d026afabc 100644 (file)
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -19,36 +19,24 @@
 extern void die (char *, struct pt_regs *, long);
 
 #ifdef CONFIG_KPROBES
-ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
-
-/* Hook to register for page fault notifications */
-int register_page_fault_notifier(struct notifier_block *nb)
+static inline int notify_page_fault(struct pt_regs *regs, int trap)
 {
-       return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
-}
+       int ret = 0;
+
+       if (!user_mode(regs)) {
+               /* kprobe_running() needs smp_processor_id() */
+               preempt_disable();
+               if (kprobe_running() && kprobes_fault_handler(regs, trap))
+                       ret = 1;
+               preempt_enable();
+       }
 
-int unregister_page_fault_notifier(struct notifier_block *nb)
-{
-       return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
-}
-
-static inline int notify_page_fault(enum die_val val, const char *str,
-                       struct pt_regs *regs, long err, int trap, int sig)
-{
-       struct die_args args = {
-               .regs = regs,
-               .str = str,
-               .err = err,
-               .trapnr = trap,
-               .signr = sig
-       };
-       return atomic_notifier_call_chain(&notify_page_fault_chain, val, &args);
+       return ret;
 }
 #else
-static inline int notify_page_fault(enum die_val val, const char *str,
-                       struct pt_regs *regs, long err, int trap, int sig)
+static inline int notify_page_fault(struct pt_regs *regs, int trap)
 {
-       return NOTIFY_DONE;
+       return 0;
 }
 #endif
 
@@ -92,6 +80,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
        struct mm_struct *mm = current->mm;
        struct siginfo si;
        unsigned long mask;
+       int fault;
 
        /* mmap_sem is performance critical.... */
        prefetchw(&mm->mmap_sem);
@@ -117,18 +106,23 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
        /*
         * This is to handle the kprobes on user space access instructions
         */
-       if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, code, TRAP_BRKPT,
-                                       SIGSEGV) == NOTIFY_STOP)
+       if (notify_page_fault(regs, TRAP_BRKPT))
                return;
 
        down_read(&mm->mmap_sem);
 
        vma = find_vma_prev(mm, address, &prev_vma);
-       if (!vma)
+       if (!vma && !prev_vma )
                goto bad_area;
 
-       /* find_vma_prev() returns vma such that address < vma->vm_end or NULL */
-       if (address < vma->vm_start)
+        /*
+         * find_vma_prev() returns vma such that address < vma->vm_end or NULL
+         *
+         * May find no vma, but could be that the last vm area is the
+         * register backing store that needs to expand upwards, in
+         * this case vma will be null, but prev_vma will ne non-null
+         */
+        if (( !vma && prev_vma ) || (address < vma->vm_start) )
                goto check_expansion;
 
   good_area:
@@ -160,31 +154,32 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
         * sure we exit gracefully rather than endlessly redo the
         * fault.
         */
-       switch (handle_mm_fault(mm, vma, address, (mask & VM_WRITE) != 0)) {
-             case VM_FAULT_MINOR:
-               ++current->min_flt;
-               break;
-             case VM_FAULT_MAJOR:
-               ++current->maj_flt;
-               break;
-             case VM_FAULT_SIGBUS:
+       fault = handle_mm_fault(mm, vma, address, (mask & VM_WRITE) != 0);
+       if (unlikely(fault & VM_FAULT_ERROR)) {
                /*
                 * We ran out of memory, or some other thing happened
                 * to us that made us unable to handle the page fault
                 * gracefully.
                 */
-               signal = SIGBUS;
-               goto bad_area;
-             case VM_FAULT_OOM:
-               goto out_of_memory;
-             default:
+               if (fault & VM_FAULT_OOM) {
+                       goto out_of_memory;
+               } else if (fault & VM_FAULT_SIGBUS) {
+                       signal = SIGBUS;
+                       goto bad_area;
+               }
                BUG();
        }
+       if (fault & VM_FAULT_MAJOR)
+               current->maj_flt++;
+       else
+               current->min_flt++;
        up_read(&mm->mmap_sem);
        return;
 
   check_expansion:
        if (!(prev_vma && (prev_vma->vm_flags & VM_GROWSUP) && (address == prev_vma->vm_end))) {
+               if (!vma)
+                       goto bad_area;
                if (!(vma->vm_flags & VM_GROWSDOWN))
                        goto bad_area;
                if (REGION_NUMBER(address) != REGION_NUMBER(vma->vm_start)