+/* Call callback for every active dquot on given filesystem */
+int dquot_scan_active(struct super_block *sb,
+ int (*fn)(struct dquot *dquot, unsigned long priv),
+ unsigned long priv)
+{
+ struct dquot *dquot, *old_dquot = NULL;
+ int ret = 0;
+
+ mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+ spin_lock(&dq_list_lock);
+ list_for_each_entry(dquot, &inuse_list, dq_inuse) {
+ if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
+ continue;
+ if (dquot->dq_sb != sb)
+ continue;
+ /* Now we have active dquot so we can just increase use count */
+ atomic_inc(&dquot->dq_count);
+ dqstats.lookups++;
+ spin_unlock(&dq_list_lock);
+ dqput(old_dquot);
+ old_dquot = dquot;
+ ret = fn(dquot, priv);
+ if (ret < 0)
+ goto out;
+ spin_lock(&dq_list_lock);
+ /* We are safe to continue now because our dquot could not
+ * be moved out of the inuse list while we hold the reference */
+ }
+ spin_unlock(&dq_list_lock);
+out:
+ dqput(old_dquot);
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+ return ret;
+}
+