[PATCH 18] introduce ptrace_set_options()

[Oleg Nesterov]

Introduce ptrace_set_options(). It will replace ptrace_setoptions() but we
can't kill the old helper yet. The new one sets ptrace_context->options, but
we should convert the code which checks ->ptrace for PT_XXX first.

Currently PTRACE_SETOPTIONS calls both helpers.

---

 kernel/ptrace.c |   38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

--- PU/kernel/ptrace.c~18_SET_OPTIONS   2009-09-02 19:53:06.000000000 +0200
+++ PU/kernel/ptrace.c  2009-09-02 20:17:34.000000000 +0200
@@ -871,6 +871,7 @@ int ptrace_writedata(struct task_struct 
        return copied;
 }
 
+/* will die soon ... */
 static int ptrace_setoptions(struct task_struct *child, long data)
 {
        child->ptrace &= ~PT_TRACE_MASK;
@@ -901,6 +902,42 @@ static int ptrace_setoptions(struct task
        return (data & ~PTRACE_O_MASK) ? -EINVAL : 0;
 }
 
+static int ptrace_set_options(struct task_struct *child, long data)
+{
+       struct utrace_engine *engine;
+       int options = 0;
+
+       if (data & PTRACE_O_TRACESYSGOOD)
+               options |= PT_TRACESYSGOOD;
+
+       if (data & PTRACE_O_TRACEFORK)
+               options |= PT_TRACE_FORK;
+
+       if (data & PTRACE_O_TRACEVFORK)
+               options |= PT_TRACE_VFORK;
+
+       if (data & PTRACE_O_TRACECLONE)
+               options |= PT_TRACE_CLONE;
+
+       if (data & PTRACE_O_TRACEEXEC)
+               options |= PT_TRACE_EXEC;
+
+       if (data & PTRACE_O_TRACEVFORKDONE)
+               options |= PT_TRACE_VFORK_DONE;
+
+       if (data & PTRACE_O_TRACEEXIT)
+               options |= PT_TRACE_EXIT;
+
+       engine = utrace_attach_task(child, UTRACE_ATTACH_MATCH_OPS,
+                                       &ptrace_utrace_ops, NULL);
+       if (likely(!IS_ERR(engine))) {
+               __ptrace_set_options(child, engine, options);
+               utrace_engine_put(engine);
+       }
+
+       return (data & ~PTRACE_O_MASK) ? -EINVAL : 0;
+}
+
 static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info)
 {
        unsigned long flags;
@@ -1139,6 +1176,7 @@ int ptrace_request(struct task_struct *c
 #endif
        case PTRACE_SETOPTIONS:
                ret = ptrace_setoptions(child, data);
+               ret = ptrace_set_options(child, data);
                break;
        case PTRACE_GETEVENTMSG:
                ret = put_user(child->ptrace_message, (unsigned long __user *) 
data);