dmaengine: virt-dma: Do not call desc_free() under a spin_lock

vchan_vdesc_fini() shouldn't be called under a spin_lock. This is done
in two places, once in vchan_terminate_vdesc() and once in
vchan_synchronize(). Instead of freeing the vdesc right away, collect
the aborted vdescs on a separate list and free them along with the other
vdescs. The terminated descs are also freed in vchan_synchronize as done
before this patch.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191216105328.15198-5-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/virt-dma.c b/drivers/dma/virt-dma.c
index 7ba7128..26e08c7 100644 (file)
--- a/drivers/dma/virt-dma.c
+++ b/drivers/dma/virt-dma.c
@@ -138,6 +138,7 @@ void vchan_init(struct virt_dma_chan *vc, struct dma_device *dmadev)
        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);
 

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index ab158ba..e213137 100644 (file)
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -31,9 +31,9 @@ struct virt_dma_chan {
        struct list_head desc_submitted;
        struct list_head desc_issued;
        struct list_head desc_completed;
+       struct list_head desc_terminated;
 
        struct virt_dma_desc *cyclic;
-       struct virt_dma_desc *vd_terminated;
 };
 
 static inline struct virt_dma_chan *to_virt_chan(struct dma_chan *chan)
@@ -141,11 +141,8 @@ static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd)
 {
        struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
 
-       /* free up stuck descriptor */
-       if (vc->vd_terminated)
-               vchan_vdesc_fini(vc->vd_terminated);
+       list_add_tail(&vd->node, &vc->desc_terminated);
 
-       vc->vd_terminated = vd;
        if (vc->cyclic == vd)
                vc->cyclic = NULL;
 }
@@ -179,6 +176,7 @@ static inline void vchan_get_all_descriptors(struct virt_dma_chan *vc,
        list_splice_tail_init(&vc->desc_submitted, head);
        list_splice_tail_init(&vc->desc_issued, head);
        list_splice_tail_init(&vc->desc_completed, head);
+       list_splice_tail_init(&vc->desc_terminated, head);
 }
 
 static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
@@ -207,16 +205,18 @@ static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
  */
 static inline void vchan_synchronize(struct virt_dma_chan *vc)
 {
+       LIST_HEAD(head);
        unsigned long flags;
 
        tasklet_kill(&vc->task);
 
        spin_lock_irqsave(&vc->lock, flags);
-       if (vc->vd_terminated) {
-               vchan_vdesc_fini(vc->vd_terminated);
-               vc->vd_terminated = NULL;
-       }
+
+       list_splice_tail_init(&vc->desc_terminated, &head);
+
        spin_unlock_irqrestore(&vc->lock, flags);
+
+       vchan_dma_desc_free_list(vc, &head);
 }
 
 #endif