Merge branch 'master' of /home/sam/kernel/linux-2.6/

[pandora-kernel.git] / arch / ia64 / kernel / kprobes.c

diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 50ae8c7..00d9c83 100644 (file)
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -23,7 +23,6 @@
  *              <anil.s.keshavamurthy@intel.com> adapted from i386
  */
 
-#include <linux/config.h>
 #include <linux/kprobes.h>
 #include <linux/ptrace.h>
 #include <linux/string.h>
@@ -34,6 +33,7 @@
 #include <asm/pgtable.h>
 #include <asm/kdebug.h>
 #include <asm/sections.h>
+#include <asm/uaccess.h>
 
 extern void jprobe_inst_return(void);
 
@@ -250,7 +250,7 @@ static void __kprobes prepare_break_inst(uint template, uint  slot,
        update_kprobe_inst_flag(template, slot, major_opcode, kprobe_inst, p);
 }
 
-static inline void get_kprobe_inst(bundle_t *bundle, uint slot,
+static void __kprobes get_kprobe_inst(bundle_t *bundle, uint slot,
                unsigned long *kprobe_inst, uint *major_opcode)
 {
        unsigned long kprobe_inst_p0, kprobe_inst_p1;
@@ -277,7 +277,7 @@ static inline void get_kprobe_inst(bundle_t *bundle, uint slot,
 }
 
 /* Returns non-zero if the addr is in the Interrupt Vector Table */
-static inline int in_ivt_functions(unsigned long addr)
+static int __kprobes in_ivt_functions(unsigned long addr)
 {
        return (addr >= (unsigned long)__start_ivt_text
                && addr < (unsigned long)__end_ivt_text);
@@ -307,19 +307,19 @@ static int __kprobes valid_kprobe_addr(int template, int slot,
        return 0;
 }
 
-static inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
+static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
 {
        kcb->prev_kprobe.kp = kprobe_running();
        kcb->prev_kprobe.status = kcb->kprobe_status;
 }
 
-static inline void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
+static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
 {
        __get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
        kcb->kprobe_status = kcb->prev_kprobe.status;
 }
 
-static inline void set_current_kprobe(struct kprobe *p,
+static void __kprobes set_current_kprobe(struct kprobe *p,
                        struct kprobe_ctlblk *kcb)
 {
        __get_cpu_var(current_kprobe) = p;
@@ -722,13 +722,50 @@ static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
        struct kprobe *cur = kprobe_running();
        struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
 
-       if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
-               return 1;
 
-       if (kcb->kprobe_status & KPROBE_HIT_SS) {
-               resume_execution(cur, regs);
-               reset_current_kprobe();
+       switch(kcb->kprobe_status) {
+       case KPROBE_HIT_SS:
+       case KPROBE_REENTER:
+               /*
+                * We are here because the instruction being single
+                * stepped caused a page fault. We reset the current
+                * kprobe and the instruction pointer points back to
+                * the probe address and allow the page fault handler
+                * to continue as a normal page fault.
+                */
+               regs->cr_iip = ((unsigned long)cur->addr) & ~0xFULL;
+               ia64_psr(regs)->ri = ((unsigned long)cur->addr) & 0xf;
+               if (kcb->kprobe_status == KPROBE_REENTER)
+                       restore_previous_kprobe(kcb);
+               else
+                       reset_current_kprobe();
                preempt_enable_no_resched();
+               break;
+       case KPROBE_HIT_ACTIVE:
+       case KPROBE_HIT_SSDONE:
+               /*
+                * We increment the nmissed count for accounting,
+                * we can also use npre/npostfault count for accouting
+                * these specific fault cases.
+                */
+               kprobes_inc_nmissed_count(cur);
+
+               /*
+                * We come here because instructions in the pre/post
+                * handler caused the page_fault, this could happen
+                * if handler tries to access user space by
+                * copy_from_user(), get_user() etc. Let the
+                * user-specified handler try to fix it first.
+                */
+               if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
+                       return 1;
+
+               /*
+                * Let ia64_do_page_fault() fix it.
+                */
+               break;
+       default:
+               break;
        }
 
        return 0;
@@ -740,6 +777,9 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
        struct die_args *args = (struct die_args *)data;
        int ret = NOTIFY_DONE;
 
+       if (args->regs && user_mode(args->regs))
+               return ret;
+
        switch(val) {
        case DIE_BREAK:
                /* err is break number from ia64_bad_break() */