Am 31.08.22 um 17:37 schrieb Dmitry Osipenko:
Move dma-buf attachment API functions to the dynamic locking specification by taking the reservation lock around the mapping operations. The strict locking convention prevents deadlock situations for dma-buf importers and exporters.
Signed-off-by: Dmitry Osipenko dmitry.osipenko@collabora.com
Reviewed-by: Christian König christian.koenig@amd.com
drivers/dma-buf/dma-buf.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index ceea4839c641..073942bf5ae9 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -858,8 +858,8 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, dma_buf_is_dynamic(dmabuf)) { struct sg_table *sgt;
dma_resv_lock(attach->dmabuf->resv, NULL);
dma_resv_lock(attach->dmabuf->resv, NULL); ret = dmabuf->ops->pin(attach); if (ret) goto err_unlock;@@ -872,8 +872,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, ret = PTR_ERR(sgt); goto err_unpin; }
if (dma_buf_is_dynamic(attach->dmabuf))dma_resv_unlock(attach->dmabuf->resv);
dma_resv_unlock(attach->dmabuf->resv);@@ -889,8 +888,7 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, dmabuf->ops->unpin(attach); err_unlock:
- if (dma_buf_is_dynamic(attach->dmabuf))
dma_resv_unlock(attach->dmabuf->resv);
- dma_resv_unlock(attach->dmabuf->resv);
dma_buf_detach(dmabuf, attach); return ERR_PTR(ret); @@ -936,21 +934,19 @@ void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) if (WARN_ON(!dmabuf || !attach)) return;
- dma_resv_lock(attach->dmabuf->resv, NULL);
- if (attach->sgt) {
if (dma_buf_is_dynamic(attach->dmabuf))dma_resv_lock(attach->dmabuf->resv, NULL);__unmap_dma_buf(attach, attach->sgt, attach->dir);
if (dma_buf_is_dynamic(attach->dmabuf)) {
if (dma_buf_is_dynamic(attach->dmabuf)) dmabuf->ops->unpin(attach);
dma_resv_unlock(attach->dmabuf->resv);}- dma_resv_lock(dmabuf->resv, NULL); list_del(&attach->node);
- dma_resv_unlock(dmabuf->resv);
- if (dmabuf->ops->detach) dmabuf->ops->detach(dmabuf, attach);