[SCSI] fcoe: moves common FCoE library API functions to libfcoe module

[safe/jmp/linux-2.6] / kernel / user.c

diff --git a/kernel/user.c b/kernel/user.c
index d476307..850e0ba 100644 (file)
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -22,7 +22,7 @@ struct user_namespace init_user_ns = {
        .kref = {
                .refcount       = ATOMIC_INIT(2),
        },
-       .root_user = &root_user,
+       .creator = &root_user,
 };
 EXPORT_SYMBOL_GPL(init_user_ns);
 
@@ -48,12 +48,14 @@ static struct kmem_cache *uid_cachep;
  */
 static DEFINE_SPINLOCK(uidhash_lock);
 
+/* root_user.__count is 2, 1 for init task cred, 1 for init_user_ns->creator */
 struct user_struct root_user = {
-       .__count        = ATOMIC_INIT(1),
+       .__count        = ATOMIC_INIT(2),
        .processes      = ATOMIC_INIT(1),
        .files          = ATOMIC_INIT(0),
        .sigpending     = ATOMIC_INIT(0),
        .locked_shm     = 0,
+       .user_ns        = &init_user_ns,
 #ifdef CONFIG_USER_SCHED
        .tg             = &init_task_group,
 #endif
@@ -70,6 +72,7 @@ static void uid_hash_insert(struct user_struct *up, struct hlist_head *hashent)
 static void uid_hash_remove(struct user_struct *up)
 {
        hlist_del_init(&up->uidhash_node);
+       put_user_ns(up->user_ns);
 }
 
 static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent)
@@ -102,6 +105,8 @@ static int sched_create_user(struct user_struct *up)
        if (IS_ERR(up->tg))
                rc = -ENOMEM;
 
+       set_tg_uid(up);
+
        return rc;
 }
 
@@ -237,13 +242,21 @@ static struct kobj_type uids_ktype = {
        .release = uids_release,
 };
 
-/* create /sys/kernel/uids/<uid>/cpu_share file for this user */
+/*
+ * 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) {
@@ -273,7 +286,7 @@ int __init uids_sysfs_init(void)
 /* work function to remove sysfs directory for a user and free up
  * corresponding structures.
  */
-static void remove_user_sysfs_dir(struct work_struct *w)
+static void cleanup_user_struct(struct work_struct *w)
 {
        struct user_struct *up = container_of(w, struct user_struct, work);
        unsigned long flags;
@@ -297,9 +310,11 @@ static void remove_user_sysfs_dir(struct work_struct *w)
        if (!remove_user)
                goto done;
 
-       kobject_uevent(&up->kobj, KOBJ_REMOVE);
-       kobject_del(&up->kobj);
-       kobject_put(&up->kobj);
+       if (up->user_ns == &init_user_ns) {
+               kobject_uevent(&up->kobj, KOBJ_REMOVE);
+               kobject_del(&up->kobj);
+               kobject_put(&up->kobj);
+       }
 
        sched_destroy_user(up);
        key_put(up->uid_keyring);
@@ -314,13 +329,13 @@ done:
  * IRQ state (as stored in flags) is restored and uidhash_lock released
  * upon function exit.
  */
-static inline void free_user(struct user_struct *up, unsigned long flags)
+static void free_user(struct user_struct *up, unsigned long flags)
 {
        /* restore back the count */
        atomic_inc(&up->__count);
        spin_unlock_irqrestore(&uidhash_lock, flags);
 
-       INIT_WORK(&up->work, remove_user_sysfs_dir);
+       INIT_WORK(&up->work, cleanup_user_struct);
        schedule_work(&up->work);
 }
 
@@ -335,7 +350,7 @@ static inline void uids_mutex_unlock(void) { }
  * IRQ state (as stored in flags) is restored and uidhash_lock released
  * upon function exit.
  */
-static inline void free_user(struct user_struct *up, unsigned long flags)
+static void free_user(struct user_struct *up, unsigned long flags)
 {
        uid_hash_remove(up);
        spin_unlock_irqrestore(&uidhash_lock, flags);
@@ -347,6 +362,24 @@ static inline void free_user(struct user_struct *up, unsigned long flags)
 
 #endif
 
+#if defined(CONFIG_RT_GROUP_SCHED) && defined(CONFIG_USER_SCHED)
+/*
+ * We need to check if a setuid can take place. This function should be called
+ * before successfully completing the setuid.
+ */
+int task_can_switch_user(struct user_struct *up, struct task_struct *tsk)
+{
+
+       return sched_rt_can_attach(up->tg, tsk);
+
+}
+#else
+int task_can_switch_user(struct user_struct *up, struct task_struct *tsk)
+{
+       return 1;
+}
+#endif
+
 /*
  * Locate the user_struct for the passed UID.  If found, take a ref on it.  The
  * caller must undo that ref with free_uid().
@@ -357,7 +390,7 @@ struct user_struct *find_user(uid_t uid)
 {
        struct user_struct *ret;
        unsigned long flags;
-       struct user_namespace *ns = current->nsproxy->user_ns;
+       struct user_namespace *ns = current_user_ns();
 
        spin_lock_irqsave(&uidhash_lock, flags);
        ret = uid_hash_find(uid, uidhashentry(ns, uid));
@@ -404,6 +437,8 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
                if (sched_create_user(new) < 0)
                        goto out_free_user;
 
+               new->user_ns = get_user_ns(ns);
+
                if (uids_user_create(new))
                        goto out_destoy_sched;
 
@@ -427,7 +462,6 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
                        up = new;
                }
                spin_unlock_irq(&uidhash_lock);
-
        }
 
        uids_mutex_unlock();
@@ -436,6 +470,7 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
 
 out_destoy_sched:
        sched_destroy_user(new);
+       put_user_ns(new->user_ns);
 out_free_user:
        kmem_cache_free(uid_cachep, new);
 out_unlock:
@@ -443,33 +478,6 @@ out_unlock:
        return NULL;
 }
 
-#ifdef CONFIG_USER_NS
-void release_uids(struct user_namespace *ns)
-{
-       int i;
-       unsigned long flags;
-       struct hlist_head *head;
-       struct hlist_node *nd;
-
-       spin_lock_irqsave(&uidhash_lock, flags);
-       /*
-        * collapse the chains so that the user_struct-s will
-        * be still alive, but not in hashes. subsequent free_uid()
-        * will free them.
-        */
-       for (i = 0; i < UIDHASH_SZ; i++) {
-               head = ns->uidhash_table + i;
-               while (!hlist_empty(head)) {
-                       nd = head->first;
-                       hlist_del_init(nd);
-               }
-       }
-       spin_unlock_irqrestore(&uidhash_lock, flags);
-
-       free_uid(ns->root_user);
-}
-#endif
-
 static int __init uid_cache_init(void)
 {
        int n;