[PATCH 3/3] dma: Add lockdep asserts to virt-dma

From: Sean Anderson
Date: Fri Mar 08 2024 - 16:01:25 EST


Add lockdep asserts to all functions with "vc.lock must be held by
caller" in their documentation. This will help catch cases where these
assumptions do not hold.

Signed-off-by: Sean Anderson <sean.anderson@xxxxxxxxx>
---

drivers/dma/virt-dma.h | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index e9f5250fbe4d..59d9eabc8b67 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -81,6 +81,8 @@ static inline struct dma_async_tx_descriptor *vchan_tx_prep(struct virt_dma_chan
*/
static inline bool vchan_issue_pending(struct virt_dma_chan *vc)
{
+ lockdep_assert_held(&vc->lock);
+
list_splice_tail_init(&vc->desc_submitted, &vc->desc_issued);
return !list_empty(&vc->desc_issued);
}
@@ -96,6 +98,8 @@ static inline void vchan_cookie_complete(struct virt_dma_desc *vd)
struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
dma_cookie_t cookie;

+ lockdep_assert_held(&vc->lock);
+
cookie = vd->tx.cookie;
dma_cookie_complete(&vd->tx);
dev_vdbg(vc->chan.device->dev, "txd %p[%x]: marked complete\n",
@@ -146,6 +150,8 @@ static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd)
{
struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);

+ lockdep_assert_held(&vc->lock);
+
list_add_tail(&vd->node, &vc->desc_terminated);

if (vc->cyclic == vd)
@@ -160,6 +166,8 @@ static inline void vchan_terminate_vdesc(struct virt_dma_desc *vd)
*/
static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
{
+ lockdep_assert_held(&vc->lock);
+
return list_first_entry_or_null(&vc->desc_issued,
struct virt_dma_desc, node);
}
@@ -177,6 +185,8 @@ static inline struct virt_dma_desc *vchan_next_desc(struct virt_dma_chan *vc)
static inline void vchan_get_all_descriptors(struct virt_dma_chan *vc,
struct list_head *head)
{
+ lockdep_assert_held(&vc->lock);
+
list_splice_tail_init(&vc->desc_allocated, head);
list_splice_tail_init(&vc->desc_submitted, head);
list_splice_tail_init(&vc->desc_issued, head);
--
2.35.1.1320.gc452695387.dirty