ptrace: s/tracehook_tracer_task()/ptrace_parent()/

tracehook.h is on the way out.  Rename tracehook_tracer_task() to
ptrace_parent() and move it from tracehook.h to ptrace.h.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>

6 files changed, 23 insertions, 23 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 9b45ee84fbcc..3a1dafd228d1 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -172,7 +172,7 @@ static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
                 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
         tpid = 0;
         if (pid_alive(p)) {
-                struct task_struct *tracer = tracehook_tracer_task(p);
+                struct task_struct *tracer = ptrace_parent(p);
                 if (tracer)
                         tpid = task_pid_nr_ns(tracer, ns);
         }
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 14def991d9dd..c883dad74b9a 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -216,7 +216,7 @@ static struct mm_struct *__check_mem_permission(struct task_struct *task)
         if (task_is_stopped_or_traced(task)) {
                 int match;
                 rcu_read_lock();
-                match = (tracehook_tracer_task(task) == current);
+                match = (ptrace_parent(task) == current);
                 rcu_read_unlock();
                 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
                         return mm;
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index b546fd6c3506..bb157bdd0c55 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -151,6 +151,24 @@ int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
                             unsigned long data);
 
 /**
+ * ptrace_parent - return the task that is tracing the given task
+ * @task: task to consider
+ *
+ * Returns %NULL if no one is tracing @task, or the &struct task_struct
+ * pointer to its tracer.
+ *
+ * Must called under rcu_read_lock().  The pointer returned might be kept
+ * live only by RCU.  During exec, this may be called with task_lock() held
+ * on @task, still held from when check_unsafe_exec() was called.
+ */
+static inline struct task_struct *ptrace_parent(struct task_struct *task)
+{
+        if (unlikely(task->ptrace))
+                return rcu_dereference(task->parent);
+        return NULL;
+}
+
+/**
  * ptrace_event_enabled - test whether a ptrace event is enabled
  * @task: ptracee of interest
  * @event: %PTRACE_EVENT_* to test
diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h
index bcc4ca762aee..7a1bd12aeffa 100644
--- a/include/linux/tracehook.h
+++ b/include/linux/tracehook.h
@@ -130,24 +130,6 @@ static inline void tracehook_report_syscall_exit(struct pt_regs *regs, int step)
 }
 
 /**
- * tracehook_tracer_task - return the task that is tracing the given task
- * @tsk:                task to consider
- *
- * Returns NULL if no one is tracing @task, or the &struct task_struct
- * pointer to its tracer.
- *
- * Must called under rcu_read_lock().  The pointer returned might be kept
- * live only by RCU.  During exec, this may be called with task_lock()
- * held on @task, still held from when tracehook_unsafe_exec() was called.
- */
-static inline struct task_struct *tracehook_tracer_task(struct task_struct *tsk)
-{
-        if (tsk->ptrace & PT_PTRACED)
-                return rcu_dereference(tsk->parent);
-        return NULL;
-}
-
-/**
  * tracehook_signal_handler - signal handler setup is complete
  * @sig:                number of signal being delivered
  * @info:               siginfo_t of signal being delivered
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index c825c6e0b636..7312bf9f7afc 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -67,7 +67,7 @@ static int may_change_ptraced_domain(struct task_struct *task,
         int error = 0;
 
         rcu_read_lock();
-        tracer = tracehook_tracer_task(task);
+        tracer = ptrace_parent(task);
         if (tracer) {
                 /* released below */
                 cred = get_task_cred(tracer);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index a0d38459d650..fc07d18ed6fc 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2048,7 +2048,7 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm)
                         u32 ptsid = 0;
 
                         rcu_read_lock();
-                        tracer = tracehook_tracer_task(current);
+                        tracer = ptrace_parent(current);
                         if (likely(tracer != NULL)) {
                                 sec = __task_cred(tracer)->security;
                                 ptsid = sec->sid;
@@ -5314,7 +5314,7 @@ static int selinux_setprocattr(struct task_struct *p,
                    Otherwise, leave SID unchanged and fail. */
                 ptsid = 0;
                 task_lock(p);
-                tracer = tracehook_tracer_task(p);
+                tracer = ptrace_parent(p);
                 if (tracer)
                         ptsid = task_sid(tracer);
                 task_unlock(p);