4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
commit bc473da1ed726c975ad47f8d7d27631de11356d8 upstream.
Descriptors that have not been acknowledged by the async_tx layer
should not be re-used, so this commit adjusts the implementation of
mv_xor_v2_prep_sw_desc() to skip descriptors for which
async_tx_test_ack() is false.
Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/mv_xor_v2.c | 32 ++++++++++++++++++++++----------
1 file changed, 22 insertions(+), 10 deletions(-)
--- a/drivers/dma/mv_xor_v2.c
+++ b/drivers/dma/mv_xor_v2.c
@@ -344,6 +344,7 @@ static struct mv_xor_v2_sw_desc *
mv_xor_v2_prep_sw_desc(struct mv_xor_v2_device *xor_dev)
{
struct mv_xor_v2_sw_desc *sw_desc;
+ bool found = false;
/* Lock the channel */
spin_lock_bh(&xor_dev->lock);
@@ -355,19 +356,23 @@ mv_xor_v2_prep_sw_desc(struct mv_xor_v2_
return NULL;
}
- /* get a free SW descriptor from the SW DESQ */
- sw_desc = list_first_entry(&xor_dev->free_sw_desc,
- struct mv_xor_v2_sw_desc, free_list);
+ list_for_each_entry(sw_desc, &xor_dev->free_sw_desc, free_list) {
+ if (async_tx_test_ack(&sw_desc->async_tx)) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ spin_unlock_bh(&xor_dev->lock);
+ return NULL;
+ }
+
list_del(&sw_desc->free_list);
/* Release the channel */
spin_unlock_bh(&xor_dev->lock);
- /* set the async tx descriptor */
- dma_async_tx_descriptor_init(&sw_desc->async_tx, &xor_dev->dmachan);
- sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit;
- async_tx_ack(&sw_desc->async_tx);
-
return sw_desc;
}
@@ -785,8 +790,15 @@ static int mv_xor_v2_probe(struct platfo
/* add all SW descriptors to the free list */
for (i = 0; i < MV_XOR_V2_DESC_NUM; i++) {
- xor_dev->sw_desq[i].idx = i;
- list_add(&xor_dev->sw_desq[i].free_list,
+ struct mv_xor_v2_sw_desc *sw_desc =
+ xor_dev->sw_desq + i;
+ sw_desc->idx = i;
+ dma_async_tx_descriptor_init(&sw_desc->async_tx,
+ &xor_dev->dmachan);
+ sw_desc->async_tx.tx_submit = mv_xor_v2_tx_submit;
+ async_tx_ack(&sw_desc->async_tx);
+
+ list_add(&sw_desc->free_list,
&xor_dev->free_sw_desc);
}