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dmaengine: stm32-mdma: use vchan_terminate_vdesc() in .terminate_all

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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 <amelie.delaunay@st.com>
Link: https://lore.kernel.org/r/20200127085334.13163-7-amelie.delaunay@st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Amelie Delaunay 2020-01-27 09:53:34 +01:00 committed by Vinod Koul
parent 542fbc463a
commit dfc708812a
1 changed files with 6 additions and 3 deletions
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9
drivers/dma/stm32-mdma.c
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@ -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;