1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index 2edb05505102..b09b75ab0751 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -35,6 +35,7 @@ struct virt_dma_chan {
         struct list_head desc_completed;
 
         struct virt_dma_desc *cyclic;
+        struct virt_dma_desc *vd_terminated;
 };
 
 static inline struct virt_dma_chan *to_virt_chan(struct dma_chan *chan)
@@ -130,6 +131,25 @@ static inline void vchan_cyclic_callback(struct virt_dma_desc *vd)
 }
 
 /**
+ * vchan_terminate_vdesc - Disable pending cyclic callback
+ * @vd: virtual descriptor to be terminated
+ *
+ * vc.lock must be held by caller
+ */
+static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd)
+{
+        struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
+
+        /* free up stuck descriptor */
+        if (vc->vd_terminated)
+                vchan_vdesc_fini(vc->vd_terminated);
+
+        vc->vd_terminated = vd;
+        if (vc->cyclic == vd)
+                vc->cyclic = NULL;
+}
+
+/**
  * vchan_next_desc - peek at the next descriptor to be processed
  * @vc: virtual channel to obtain descriptor from
  *
@@ -182,10 +202,20 @@ static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
  * Makes sure that all scheduled or active callbacks have finished running. For
  * proper operation the caller has to ensure that no new callbacks are scheduled
  * after the invocation of this function started.
+ * Free up the terminated cyclic descriptor to prevent memory leakage.
  */
 static inline void vchan_synchronize(struct virt_dma_chan *vc)
 {
+        unsigned long flags;
+
         tasklet_kill(&vc->task);
+
+        spin_lock_irqsave(&vc->lock, flags);
+        if (vc->vd_terminated) {
+                vchan_vdesc_fini(vc->vd_terminated);
+                vc->vd_terminated = NULL;
+        }
+        spin_unlock_irqrestore(&vc->lock, flags);
 }
 
 #endif