+static void uid_hash_insert(struct user_struct *up, struct hlist_head *hashent)
+{
+ hlist_add_head(&up->uidhash_node, hashent);
+}
+
+static void uid_hash_remove(struct user_struct *up)
+{
+ hlist_del_init(&up->uidhash_node);
+ put_user_ns(up->user_ns);
+}
+
+#ifdef CONFIG_USER_SCHED
+
+static void sched_destroy_user(struct user_struct *up)
+{
+ sched_destroy_group(up->tg);
+}
+
+static int sched_create_user(struct user_struct *up)
+{
+ int rc = 0;
+
+ up->tg = sched_create_group(&root_task_group);
+ if (IS_ERR(up->tg))
+ rc = -ENOMEM;
+
+ set_tg_uid(up);
+
+ return rc;
+}
+
+#else /* CONFIG_USER_SCHED */
+
+static void sched_destroy_user(struct user_struct *up) { }
+static int sched_create_user(struct user_struct *up) { return 0; }
+
+#endif /* CONFIG_USER_SCHED */
+
+#if defined(CONFIG_USER_SCHED) && defined(CONFIG_SYSFS)
+
+static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent)
+{
+ struct user_struct *user;
+ struct hlist_node *h;
+
+ hlist_for_each_entry(user, h, hashent, uidhash_node) {
+ if (user->uid == uid) {
+ /* possibly resurrect an "almost deleted" object */
+ if (atomic_inc_return(&user->__count) == 1)
+ cancel_delayed_work(&user->work);
+ return user;
+ }
+ }
+
+ return NULL;
+}
+
+static struct kset *uids_kset; /* represents the /sys/kernel/uids/ directory */
+static DEFINE_MUTEX(uids_mutex);
+
+static inline void uids_mutex_lock(void)
+{
+ mutex_lock(&uids_mutex);
+}
+
+static inline void uids_mutex_unlock(void)
+{
+ mutex_unlock(&uids_mutex);
+}
+
+/* uid directory attributes */
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static ssize_t cpu_shares_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+
+ return sprintf(buf, "%lu\n", sched_group_shares(up->tg));
+}
+
+static ssize_t cpu_shares_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+ unsigned long shares;
+ int rc;
+
+ sscanf(buf, "%lu", &shares);
+
+ rc = sched_group_set_shares(up->tg, shares);
+
+ return (rc ? rc : size);
+}
+
+static struct kobj_attribute cpu_share_attr =
+ __ATTR(cpu_share, 0644, cpu_shares_show, cpu_shares_store);
+#endif
+
+#ifdef CONFIG_RT_GROUP_SCHED
+static ssize_t cpu_rt_runtime_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+
+ return sprintf(buf, "%ld\n", sched_group_rt_runtime(up->tg));
+}
+
+static ssize_t cpu_rt_runtime_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+ unsigned long rt_runtime;
+ int rc;
+
+ sscanf(buf, "%ld", &rt_runtime);
+
+ rc = sched_group_set_rt_runtime(up->tg, rt_runtime);
+
+ return (rc ? rc : size);
+}
+
+static struct kobj_attribute cpu_rt_runtime_attr =
+ __ATTR(cpu_rt_runtime, 0644, cpu_rt_runtime_show, cpu_rt_runtime_store);
+
+static ssize_t cpu_rt_period_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+
+ return sprintf(buf, "%lu\n", sched_group_rt_period(up->tg));
+}
+
+static ssize_t cpu_rt_period_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct user_struct *up = container_of(kobj, struct user_struct, kobj);
+ unsigned long rt_period;
+ int rc;
+
+ sscanf(buf, "%lu", &rt_period);
+
+ rc = sched_group_set_rt_period(up->tg, rt_period);
+
+ return (rc ? rc : size);
+}
+
+static struct kobj_attribute cpu_rt_period_attr =
+ __ATTR(cpu_rt_period, 0644, cpu_rt_period_show, cpu_rt_period_store);
+#endif
+
+/* default attributes per uid directory */
+static struct attribute *uids_attributes[] = {
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ &cpu_share_attr.attr,
+#endif
+#ifdef CONFIG_RT_GROUP_SCHED
+ &cpu_rt_runtime_attr.attr,
+ &cpu_rt_period_attr.attr,
+#endif
+ NULL
+};
+
+/* the lifetime of user_struct is not managed by the core (now) */
+static void uids_release(struct kobject *kobj)
+{
+ return;
+}
+
+static struct kobj_type uids_ktype = {
+ .sysfs_ops = &kobj_sysfs_ops,
+ .default_attrs = uids_attributes,
+ .release = uids_release,
+};
+
+/*
+ * Create /sys/kernel/uids/<uid>/cpu_share file for this user
+ * We do not create this file for users in a user namespace (until
+ * sysfs tagging is implemented).
+ *
+ * See Documentation/scheduler/sched-design-CFS.txt for ramifications.
+ */
+static int uids_user_create(struct user_struct *up)
+{
+ struct kobject *kobj = &up->kobj;
+ int error;
+
+ memset(kobj, 0, sizeof(struct kobject));
+ if (up->user_ns != &init_user_ns)
+ return 0;
+ kobj->kset = uids_kset;
+ error = kobject_init_and_add(kobj, &uids_ktype, NULL, "%d", up->uid);
+ if (error) {
+ kobject_put(kobj);
+ goto done;
+ }
+
+ kobject_uevent(kobj, KOBJ_ADD);
+done:
+ return error;
+}
+
+/* create these entries in sysfs:
+ * "/sys/kernel/uids" directory
+ * "/sys/kernel/uids/0" directory (for root user)
+ * "/sys/kernel/uids/0/cpu_share" file (for root user)
+ */
+int __init uids_sysfs_init(void)