ipc,msg: provide barrier pairings for lockless receive

[cascardo/linux.git] / drivers / dma / virt-dma.h

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index 181b952..189e75d 100644 (file)
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -29,6 +29,7 @@ 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;
@@ -55,11 +56,16 @@ 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;
 }
 
@@ -122,7 +128,8 @@ static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
 }
 
 /**
- * vchan_get_all_descriptors - obtain all submitted and issued descriptors
+ * vchan_get_all_descriptors - obtain all allocated, submitted and issued
+ *                             descriptors
  * vc: virtual channel to get descriptors from
  * head: list of descriptors found
  *
@@ -134,6 +141,7 @@ 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);
@@ -141,11 +149,14 @@ 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);