userns: Replace user_ns_map_uid and user_ns_map_gid with from_kuid and from_kgid

These function are no longer needed replace them with their more useful equivalents.
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

include/linux/user_namespace.h

@@ -69,16 +69,4 @@ static inline void put_user_ns(struct user_namespace *ns)
 
 #endif
 
-static inline uid_t user_ns_map_uid(struct user_namespace *to,
-	const struct cred *cred, kuid_t uid)
-{
-	return from_kuid_munged(to, uid);
-}
-
-static inline gid_t user_ns_map_gid(struct user_namespace *to,
-	const struct cred *cred, kgid_t gid)
-{
-	return from_kgid_munged(to, gid);
-}
-
 #endif /* _LINUX_USER_H */

ipc/mqueue.c

@@ -538,8 +538,7 @@ static void __do_notify(struct mqueue_inode_info *info)
 			rcu_read_lock();
 			sig_i.si_pid = task_tgid_nr_ns(current,
 						ns_of_pid(info->notify_owner));
-			sig_i.si_uid = user_ns_map_uid(info->notify_user_ns,
-						current_cred(), current_uid());
+			sig_i.si_uid = from_kuid_munged(info->notify_user_ns, current_uid());
 			rcu_read_unlock();
 
 			kill_pid_info(info->notify.sigev_signo,

kernel/signal.c

@@ -1026,7 +1026,7 @@ static inline int legacy_queue(struct sigpending *signals, int sig)
 static inline uid_t map_cred_ns(const struct cred *cred,
 				struct user_namespace *ns)
 {
-	return user_ns_map_uid(ns, cred, cred->uid);
+	return from_kuid_munged(ns, cred->uid);
 }
 
 #ifdef CONFIG_USER_NS

net/core/sock.c

@@ -821,8 +821,8 @@ void cred_to_ucred(struct pid *pid, const struct cred *cred,
 	if (cred) {
 		struct user_namespace *current_ns = current_user_ns();
 
-		ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
-		ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
+		ucred->uid = from_kuid(current_ns, cred->euid);
+		ucred->gid = from_kgid(current_ns, cred->egid);
 	}
 }
 EXPORT_SYMBOL_GPL(cred_to_ucred);