1 files changed, 49 insertions, 29 deletions

diff --git a/drivers/dma/virt-dma.c b/drivers/dma/virt-dma.c
index 6f80432a3f0a..7961172a780d 100644
--- a/drivers/dma/virt-dma.c
+++ b/drivers/dma/virt-dma.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Virtual DMA channel support for DMAengine
  *
  * Copyright (C) 2012 Russell King
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 #include <linux/device.h>
 #include <linux/dmaengine.h>
@@ -29,7 +26,7 @@ dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *tx)
 	spin_lock_irqsave(&vc->lock, flags);
 	cookie = dma_cookie_assign(tx);
 
-	list_add_tail(&vd->node, &vc->desc_submitted);
+	list_move_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",
@@ -39,6 +36,33 @@ dma_cookie_t vchan_tx_submit(struct dma_async_tx_descriptor *tx)
 }
 EXPORT_SYMBOL_GPL(vchan_tx_submit);
 
+/**
+ * vchan_tx_desc_free - free a reusable descriptor
+ * @tx: the transfer
+ *
+ * This function frees a previously allocated reusable descriptor. The only
+ * other way is to clear the DMA_CTRL_REUSE flag and submit one last time the
+ * transfer.
+ *
+ * Returns 0 upon success
+ */
+int vchan_tx_desc_free(struct dma_async_tx_descriptor *tx)
+{
+	struct virt_dma_chan *vc = to_virt_chan(tx->chan);
+	struct virt_dma_desc *vd = to_virt_desc(tx);
+	unsigned long flags;
+
+	spin_lock_irqsave(&vc->lock, flags);
+	list_del(&vd->node);
+	spin_unlock_irqrestore(&vc->lock, flags);
+
+	dev_dbg(vc->chan.device->dev, "vchan %p: txd %p[%x]: freeing\n",
+		vc, vd, vd->tx.cookie);
+	vc->desc_free(vd);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(vchan_tx_desc_free);
+
 struct virt_dma_desc *vchan_find_desc(struct virt_dma_chan *vc,
 	dma_cookie_t cookie)
 {
@@ -56,12 +80,11 @@ EXPORT_SYMBOL_GPL(vchan_find_desc);
  * This tasklet handles the completion of a DMA descriptor by
  * calling its callback and freeing it.
  */
-static void vchan_complete(unsigned long arg)
+static void vchan_complete(struct tasklet_struct *t)
 {
-	struct virt_dma_chan *vc = (struct virt_dma_chan *)arg;
-	struct virt_dma_desc *vd;
-	dma_async_tx_callback cb = NULL;
-	void *cb_data = NULL;
+	struct virt_dma_chan *vc = from_tasklet(vc, t, task);
+	struct virt_dma_desc *vd, *_vd;
+	struct dmaengine_desc_callback cb;
 	LIST_HEAD(head);
 
 	spin_lock_irq(&vc->lock);
@@ -69,36 +92,30 @@ static void vchan_complete(unsigned long arg)
 	vd = vc->cyclic;
 	if (vd) {
 		vc->cyclic = NULL;
-		cb = vd->tx.callback;
-		cb_data = vd->tx.callback_param;
+		dmaengine_desc_get_callback(&vd->tx, &cb);
+	} else {
+		memset(&cb, 0, sizeof(cb));
 	}
 	spin_unlock_irq(&vc->lock);
 
-	if (cb)
-		cb(cb_data);
+	dmaengine_desc_callback_invoke(&cb, &vd->tx_result);
 
-	while (!list_empty(&head)) {
-		vd = list_first_entry(&head, struct virt_dma_desc, node);
-		cb = vd->tx.callback;
-		cb_data = vd->tx.callback_param;
+	list_for_each_entry_safe(vd, _vd, &head, node) {
+		dmaengine_desc_get_callback(&vd->tx, &cb);
 
 		list_del(&vd->node);
-
-		vc->desc_free(vd);
-
-		if (cb)
-			cb(cb_data);
+		dmaengine_desc_callback_invoke(&cb, &vd->tx_result);
+		vchan_vdesc_fini(vd);
 	}
 }
 
 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);
+	struct virt_dma_desc *vd, *_vd;
+
+	list_for_each_entry_safe(vd, _vd, head, node) {
 		list_del(&vd->node);
-		dev_dbg(vc->chan.device->dev, "txd %p: freeing\n", vd);
-		vc->desc_free(vd);
+		vchan_vdesc_fini(vd);
 	}
 }
 EXPORT_SYMBOL_GPL(vchan_dma_desc_free_list);
@@ -108,11 +125,13 @@ 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);
+	INIT_LIST_HEAD(&vc->desc_terminated);
 
-	tasklet_init(&vc->task, vchan_complete, (unsigned long)vc);
+	tasklet_setup(&vc->task, vchan_complete);
 
 	vc->chan.device = dmadev;
 	list_add_tail(&vc->chan.device_node, &dmadev->channels);
@@ -120,4 +139,5 @@ void vchan_init(struct virt_dma_chan *vc, struct dma_device *dmadev)
 EXPORT_SYMBOL_GPL(vchan_init);
 
 MODULE_AUTHOR("Russell King");
+MODULE_DESCRIPTION("Virtual DMA channel support for DMAengine");
 MODULE_LICENSE("GPL");