@@ -111,6 +111,7 @@ static void hidma_process_completed(struct hidma_chan *mchan)
struct dma_async_tx_descriptor *desc;
dma_cookie_t last_cookie;
struct hidma_desc *mdesc;
+ struct hidma_desc *next;
unsigned long irqflags;
struct list_head list;
@@ -122,8 +123,9 @@ static void hidma_process_completed(struct hidma_chan *mchan)
spin_unlock_irqrestore(&mchan->lock, irqflags);
/* Execute callbacks and run dependencies */
- list_for_each_entry(mdesc, &list, node) {
+ list_for_each_entry_safe(mdesc, next, &list, node) {
enum dma_status llstat;
+ struct dmaengine_desc_callback cb;
desc = &mdesc->desc;
@@ -132,18 +134,18 @@ static void hidma_process_completed(struct hidma_chan *mchan)
spin_unlock_irqrestore(&mchan->lock, irqflags);
llstat = hidma_ll_status(mdma->lldev, mdesc->tre_ch);
- if (llstat == DMA_COMPLETE)
- dmaengine_desc_get_callback_invoke(desc, NULL);
+ dmaengine_desc_get_callback(desc, &cb);
last_cookie = desc->cookie;
dma_run_dependencies(desc);
- }
- /* Free descriptors */
- spin_lock_irqsave(&mchan->lock, irqflags);
- list_splice_tail_init(&list, &mchan->free);
- spin_unlock_irqrestore(&mchan->lock, irqflags);
+ spin_lock_irqsave(&mchan->lock, irqflags);
+ list_move(&mdesc->node, &mchan->free);
+ spin_unlock_irqrestore(&mchan->lock, irqflags);
+ if (llstat == DMA_COMPLETE)
+ dmaengine_desc_callback_invoke(&cb, NULL);
+ }
}
/*
There is a race condition between data transfer callback and descriptor free code. The callback routine may decide to clear the resources even though the descriptor has not yet been freed. Instead of calling the callback first and then releasing the memory, this code is changing the order to return the descriptor back to the free pool and then call the user provided callback. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> --- drivers/dma/qcom/hidma.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)