+
+/*
+ * The recovery_list is a simple linked list of node numbers to recover.
+ * It is protected by the recovery_lock.
+ */
+
+struct ocfs2_recovery_map {
+ unsigned int rm_used;
+ unsigned int *rm_entries;
+};
+
+int ocfs2_recovery_init(struct ocfs2_super *osb)
+{
+ struct ocfs2_recovery_map *rm;
+
+ mutex_init(&osb->recovery_lock);
+ osb->disable_recovery = 0;
+ osb->recovery_thread_task = NULL;
+ init_waitqueue_head(&osb->recovery_event);
+
+ rm = kzalloc(sizeof(struct ocfs2_recovery_map) +
+ osb->max_slots * sizeof(unsigned int),
+ GFP_KERNEL);
+ if (!rm) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ rm->rm_entries = (unsigned int *)((char *)rm +
+ sizeof(struct ocfs2_recovery_map));
+ osb->recovery_map = rm;
+
+ return 0;
+}
+
+/* we can't grab the goofy sem lock from inside wait_event, so we use
+ * memory barriers to make sure that we'll see the null task before
+ * being woken up */
+static int ocfs2_recovery_thread_running(struct ocfs2_super *osb)
+{
+ mb();
+ return osb->recovery_thread_task != NULL;
+}
+
+void ocfs2_recovery_exit(struct ocfs2_super *osb)
+{
+ struct ocfs2_recovery_map *rm;
+
+ /* disable any new recovery threads and wait for any currently
+ * running ones to exit. Do this before setting the vol_state. */
+ mutex_lock(&osb->recovery_lock);
+ osb->disable_recovery = 1;
+ mutex_unlock(&osb->recovery_lock);
+ wait_event(osb->recovery_event, !ocfs2_recovery_thread_running(osb));
+
+ /* At this point, we know that no more recovery threads can be
+ * launched, so wait for any recovery completion work to
+ * complete. */
+ flush_workqueue(ocfs2_wq);
+
+ /*
+ * Now that recovery is shut down, and the osb is about to be
+ * freed, the osb_lock is not taken here.
+ */
+ rm = osb->recovery_map;
+ /* XXX: Should we bug if there are dirty entries? */
+
+ kfree(rm);
+}
+
+static int __ocfs2_recovery_map_test(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ int i;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ assert_spin_locked(&osb->osb_lock);
+
+ for (i = 0; i < rm->rm_used; i++) {
+ if (rm->rm_entries[i] == node_num)
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Behaves like test-and-set. Returns the previous value */
+static int ocfs2_recovery_map_set(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ spin_lock(&osb->osb_lock);
+ if (__ocfs2_recovery_map_test(osb, node_num)) {
+ spin_unlock(&osb->osb_lock);
+ return 1;
+ }
+
+ /* XXX: Can this be exploited? Not from o2dlm... */
+ BUG_ON(rm->rm_used >= osb->max_slots);
+
+ rm->rm_entries[rm->rm_used] = node_num;
+ rm->rm_used++;
+ spin_unlock(&osb->osb_lock);
+
+ return 0;
+}
+
+static void ocfs2_recovery_map_clear(struct ocfs2_super *osb,
+ unsigned int node_num)
+{
+ int i;
+ struct ocfs2_recovery_map *rm = osb->recovery_map;
+
+ spin_lock(&osb->osb_lock);
+
+ for (i = 0; i < rm->rm_used; i++) {
+ if (rm->rm_entries[i] == node_num)
+ break;
+ }
+
+ if (i < rm->rm_used) {
+ /* XXX: be careful with the pointer math */
+ memmove(&(rm->rm_entries[i]), &(rm->rm_entries[i + 1]),
+ (rm->rm_used - i - 1) * sizeof(unsigned int));
+ rm->rm_used--;
+ }
+
+ spin_unlock(&osb->osb_lock);
+}
+