Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds

[linux-2.6-omap-h63xx.git] / arch / powerpc / mm / fault.c

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 03aeb3a460772528b009e3f240e735ffd463047d..ab3546c5ac3a2a8f4b022ba8150c13a9c7686728 100644 (file)
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -28,6 +28,7 @@
 #include <linux/highmem.h>
 #include <linux/module.h>
 #include <linux/kprobes.h>
+#include <linux/kdebug.h>
 
 #include <asm/page.h>
 #include <asm/pgtable.h>
@@ -36,40 +37,28 @@
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include <asm/tlbflush.h>
-#include <asm/kdebug.h>
 #include <asm/siginfo.h>
 
-#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)
-{
-       return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
-}
 
-int unregister_page_fault_notifier(struct notifier_block *nb)
+#ifdef CONFIG_KPROBES
+static inline int notify_page_fault(struct pt_regs *regs)
 {
-       return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
-}
+       int ret = 0;
+
+       /* kprobe_running() needs smp_processor_id() */
+       if (!user_mode(regs)) {
+               preempt_disable();
+               if (kprobe_running() && kprobe_fault_handler(regs, 11))
+                       ret = 1;
+               preempt_enable();
+       }
 
-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)
 {
-       return NOTIFY_DONE;
+       return 0;
 }
 #endif
 
@@ -156,7 +145,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
        struct mm_struct *mm = current->mm;
        siginfo_t info;
        int code = SEGV_MAPERR;
-       int is_write = 0;
+       int is_write = 0, ret;
        int trap = TRAP(regs);
        int is_exec = trap == 0x400;
 
@@ -175,8 +164,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
        is_write = error_code & ESR_DST;
 #endif /* CONFIG_4xx || CONFIG_BOOKE */
 
-       if (notify_page_fault(DIE_PAGE_FAULT, "page_fault", regs, error_code,
-                               11, SIGSEGV) == NOTIFY_STOP)
+       if (notify_page_fault(regs))
                return 0;
 
        if (trap == 0x300) {
@@ -291,14 +279,19 @@ good_area:
 #endif /* CONFIG_8xx */
 
        if (is_exec) {
-#ifdef CONFIG_PPC64
+#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
                /* protection fault */
                if (error_code & DSISR_PROTFAULT)
                        goto bad_area;
-               if (!(vma->vm_flags & VM_EXEC))
+               /*
+                * Allow execution from readable areas if the MMU does not
+                * provide separate controls over reading and executing.
+                */
+               if (!(vma->vm_flags & VM_EXEC) &&
+                   (cpu_has_feature(CPU_FTR_NOEXECUTE) ||
+                    !(vma->vm_flags & (VM_READ | VM_WRITE))))
                        goto bad_area;
-#endif
-#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
+#else
                pte_t *ptep;
                pmd_t *pmdp;
 
@@ -343,22 +336,18 @@ good_area:
         * the fault.
         */
  survive:
-       switch (handle_mm_fault(mm, vma, address, is_write)) {
-
-       case VM_FAULT_MINOR:
-               current->min_flt++;
-               break;
-       case VM_FAULT_MAJOR:
-               current->maj_flt++;
-               break;
-       case VM_FAULT_SIGBUS:
-               goto do_sigbus;
-       case VM_FAULT_OOM:
-               goto out_of_memory;
-       default:
+       ret = handle_mm_fault(mm, vma, address, is_write);
+       if (unlikely(ret & VM_FAULT_ERROR)) {
+               if (ret & VM_FAULT_OOM)
+                       goto out_of_memory;
+               else if (ret & VM_FAULT_SIGBUS)
+                       goto do_sigbus;
                BUG();
        }
-
+       if (ret & VM_FAULT_MAJOR)
+               current->maj_flt++;
+       else
+               current->min_flt++;
        up_read(&mm->mmap_sem);
        return 0;
 
@@ -393,7 +382,7 @@ out_of_memory:
        }
        printk("VM: killing process %s\n", current->comm);
        if (user_mode(regs))
-               do_exit(SIGKILL);
+               do_group_exit(SIGKILL);
        return SIGKILL;
 
 do_sigbus: