+
+ /*
+ * With per-cpu counters, this becomes an interesting
+ * problem. we needto work out if we are freeing or allocation
+ * blocks first, then we can do the modification as necessary.
+ *
+ * We do this under the m_sb_lock so that if we are near
+ * ENOSPC, we will hold out any changes while we work out
+ * what to do. This means that the amount of free space can
+ * change while we do this, so we need to retry if we end up
+ * trying to reserve more space than is available.
+ *
+ * We also use the xfs_mod_incore_sb() interface so that we
+ * don't have to care about whether per cpu counter are
+ * enabled, disabled or even compiled in....
+ */
+retry:
+ spin_lock(&mp->m_sb_lock);
+ xfs_icsb_sync_counters_locked(mp, 0);