Revert "dmaengine: virt-dma: don't always free descriptor upon completion"

This reverts commit b9855f03d560d351e95301b9de0bc3cad3b31fe9.
The patch break existing DMA usage case. For example, audio SOC
dmaengine never release channel and cause virt-dma to cache too
much memory in descriptor to exhaust system memory.

Signed-off-by: Vinod Koul <vinod.koul@intel.com>

2 files changed, 7 insertions, 25 deletions

diff --git a/drivers/dma/virt-dma.c b/drivers/dma/virt-dma.c
index 7d2c17d8d30f..6f80432a3f0a 100644
--- a/drivers/dma/virt-dma.c
+++ b/drivers/dma/virt-dma.c
@@ -29,7 +29,7 @@ dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *tx)
         spin_lock_irqsave(&vc->lock, flags);
         cookie = dma_cookie_assign(tx);
 
-        list_move_tail(&vd->node, &vc->desc_submitted);
+        list_add_tail(&vd->node, &vc->desc_submitted);
         spin_unlock_irqrestore(&vc->lock, flags);
 
         dev_dbg(vc->chan.device->dev, "vchan %p: txd %p[%x]: submitted\n",
@@ -83,10 +83,8 @@ static void vchan_complete(unsigned long arg)
                 cb_data = vd->tx.callback_param;
 
                 list_del(&vd->node);
-                if (async_tx_test_ack(&vd->tx))
-                        list_add(&vd->node, &vc->desc_allocated);
-                else
-                        vc->desc_free(vd);
+
+                vc->desc_free(vd);
 
                 if (cb)
                         cb(cb_data);
@@ -98,13 +96,9 @@ void vchan_dma_desc_free_list(struct virt_dma_chan *vc, struct list_head *head)
         while (!list_empty(head)) {
                 struct virt_dma_desc *vd = list_first_entry(head,
                         struct virt_dma_desc, node);
-                if (async_tx_test_ack(&vd->tx)) {
-                        list_move_tail(&vd->node, &vc->desc_allocated);
-                } else {
-                        dev_dbg(vc->chan.device->dev, "txd %p: freeing\n", vd);
-                        list_del(&vd->node);
-                        vc->desc_free(vd);
-                }
+                list_del(&vd->node);
+                dev_dbg(vc->chan.device->dev, "txd %p: freeing\n", vd);
+                vc->desc_free(vd);
         }
 }
 EXPORT_SYMBOL_GPL(vchan_dma_desc_free_list);
@@ -114,7 +108,6 @@ void vchan_init(struct virt_dma_chan *vc, struct dma_device *dmadev)
         dma_cookie_init(&vc->chan);
 
         spin_lock_init(&vc->lock);
-        INIT_LIST_HEAD(&vc->desc_allocated);
         INIT_LIST_HEAD(&vc->desc_submitted);
         INIT_LIST_HEAD(&vc->desc_issued);
         INIT_LIST_HEAD(&vc->desc_completed);
diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index 189e75dbcb15..181b95267866 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -29,7 +29,6 @@ struct virt_dma_chan {
         spinlock_t lock;
 
         /* protected by vc.lock */
-        struct list_head desc_allocated;
         struct list_head desc_submitted;
         struct list_head desc_issued;
         struct list_head desc_completed;
@@ -56,16 +55,11 @@ static inline struct dma_async_tx_descriptor *vchan_tx_prep(struct virt_dma_chan
         struct virt_dma_desc *vd, unsigned long tx_flags)
 {
         extern dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *);
-        unsigned long flags;
 
         dma_async_tx_descriptor_init(&vd->tx, &vc->chan);
         vd->tx.flags = tx_flags;
         vd->tx.tx_submit = vchan_tx_submit;
 
-        spin_lock_irqsave(&vc->lock, flags);
-        list_add_tail(&vd->node, &vc->desc_allocated);
-        spin_unlock_irqrestore(&vc->lock, flags);
-
         return &vd->tx;
 }
 
@@ -128,8 +122,7 @@ static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
 }
 
 /**
- * vchan_get_all_descriptors - obtain all allocated, submitted and issued
- *                             descriptors
+ * vchan_get_all_descriptors - obtain all submitted and issued descriptors
  * vc: virtual channel to get descriptors from
  * head: list of descriptors found
  *
@@ -141,7 +134,6 @@ static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
 static inline void vchan_get_all_descriptors(struct virt_dma_chan *vc,
         struct list_head *head)
 {
-        list_splice_tail_init(&vc->desc_allocated, head);
         list_splice_tail_init(&vc->desc_submitted, head);
         list_splice_tail_init(&vc->desc_issued, head);
         list_splice_tail_init(&vc->desc_completed, head);
@@ -149,14 +141,11 @@ static inline void vchan_get_all_descriptors(struct virt_dma_chan *vc,
 
 static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
 {
-        struct virt_dma_desc *vd;
         unsigned long flags;
         LIST_HEAD(head);
 
         spin_lock_irqsave(&vc->lock, flags);
         vchan_get_all_descriptors(vc, &head);
-        list_for_each_entry(vd, &head, node)
-                async_tx_clear_ack(&vd->tx);
         spin_unlock_irqrestore(&vc->lock, flags);
 
         vchan_dma_desc_free_list(vc, &head);