most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set

Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/kernel/signal.c b/kernel/signal.c
index b9be7e0..df8d721 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2524,7 +2524,16 @@
  * It is wrong to change ->blocked directly, this helper should be used
  * to ensure the process can't miss a shared signal we are going to block.
  */
-void set_current_blocked(const sigset_t *newset)
+void set_current_blocked(sigset_t *newset)
+{
+	struct task_struct *tsk = current;
+	sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP));
+	spin_lock_irq(&tsk->sighand->siglock);
+	__set_task_blocked(tsk, newset);
+	spin_unlock_irq(&tsk->sighand->siglock);
+}
+
+void __set_current_blocked(const sigset_t *newset)
 {
 	struct task_struct *tsk = current;
 
@@ -2564,7 +2573,7 @@
 		return -EINVAL;
 	}
 
-	set_current_blocked(&newset);
+	__set_current_blocked(&newset);
 	return 0;
 }
 
@@ -3138,7 +3147,7 @@
 			return -EINVAL;
 		}
 
-		set_current_blocked(&new_blocked);
+		__set_current_blocked(&new_blocked);
 	}
 
 	if (oset) {
@@ -3202,7 +3211,6 @@
 	int old = current->blocked.sig[0];
 	sigset_t newset;
 
-	siginitset(&newset, newmask & ~(sigmask(SIGKILL) | sigmask(SIGSTOP)));
 	set_current_blocked(&newset);
 
 	return old;
@@ -3243,8 +3251,6 @@
 
 int sigsuspend(sigset_t *set)
 {
-	sigdelsetmask(set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
 	current->saved_sigmask = current->blocked;
 	set_current_blocked(set);