[PATCH] ppc64: Add ptrace data breakpoint support

Add hardware data breakpoint support.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 25 insertions, 6 deletions

diff --git a/arch/ppc64/mm/fault.c b/arch/ppc64/mm/fault.c
index 772f0714a5b7..7fbc68bbb739 100644
--- a/arch/ppc64/mm/fault.c
+++ b/arch/ppc64/mm/fault.c
@@ -77,6 +77,28 @@ static int store_updates_sp(struct pt_regs *regs)
         return 0;
 }
 
+static void do_dabr(struct pt_regs *regs, unsigned long error_code)
+{
+        siginfo_t info;
+
+        if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
+                        11, SIGSEGV) == NOTIFY_STOP)
+                return;
+
+        if (debugger_dabr_match(regs))
+                return;
+
+        /* Clear the DABR */
+        set_dabr(0);
+
+        /* Deliver the signal to userspace */
+        info.si_signo = SIGTRAP;
+        info.si_errno = 0;
+        info.si_code = TRAP_HWBKPT;
+        info.si_addr = (void __user *)regs->nip;
+        force_sig_info(SIGTRAP, &info, current);
+}
+
 /*
  * The error_code parameter is
  *  - DSISR for a non-SLB data access fault,
@@ -111,12 +133,9 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
         if (!user_mode(regs) && (address >= TASK_SIZE))
                 return SIGSEGV;
 
-        if (error_code & DSISR_DABRMATCH) {
-                if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
-                                        11, SIGSEGV) == NOTIFY_STOP)
-                        return 0;
-                if (debugger_dabr_match(regs))
-                        return 0;
+        if (error_code & DSISR_DABRMATCH) {
+                do_dabr(regs, error_code);
+                return 0;
         }
 
         if (in_atomic() || mm == NULL) {