[6/6] dmaengine: stm32-mdma: use vchan_terminate_vdesc() in .terminate_all

Commit Message

Amelie Delaunay Jan. 27, 2020, 8:53 a.m. UTC

To avoid race with vchan_complete, use the race free way to terminate
running transfer.

Move vdesc->node list_del in stm32_mdma_start_transfer instead of in
stm32_mdma_xfer_end to avoid another race in vchan_dma_desc_free_list.

Signed-off-by: Amelie Delaunay <[e-mail]>
---
 drivers/dma/stm32-mdma.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Patch

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index f2043f47ae9e..5469563703d1 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1126,6 +1126,8 @@  static void stm32_mdma_start_transfer(struct stm32_mdma_chan *chan)
 		return;
 	}
 
+	list_del(&vdesc->node);
+
 	chan->desc = to_stm32_mdma_desc(vdesc);
 	hwdesc = chan->desc->node[0].hwdesc;
 	chan->curr_hwdesc = 0;
@@ -1241,8 +1243,10 @@  static int stm32_mdma_terminate_all(struct dma_chan *c)
 	LIST_HEAD(head);
 
 	spin_lock_irqsave(&chan->vchan.lock, flags);
-	if (chan->busy) {
-		stm32_mdma_stop(chan);
+	if (chan->desc) {
+		vchan_terminate_vdesc(&chan->desc->vdesc);
+		if (chan->busy)
+			stm32_mdma_stop(chan);
 		chan->desc = NULL;
 	}
 	vchan_get_all_descriptors(&chan->vchan, &head);
@@ -1330,7 +1334,6 @@  static enum dma_status stm32_mdma_tx_status(struct dma_chan *c,
 
 static void stm32_mdma_xfer_end(struct stm32_mdma_chan *chan)
 {
-	list_del(&chan->desc->vdesc.node);
 	vchan_cookie_complete(&chan->desc->vdesc);
 	chan->desc = NULL;
 	chan->busy = false;