On Thu, Sep 17, 2026 at 10:38:25AM +0300, Laurent Pinchart wrote:
> On Thu, Sep 17, 2026 at 09:12:07AM +0200, Wolfram Sang wrote:
> > From: Koichiro Den <den@valinux.co.jp>
> > 
> > Call dma_descriptor_unmap() right after dma_cookie_complete() in the
> > threaded IRQ completion path. Without this, streaming DMA mappings
> > attached to the descriptor are never released and may eventually exhaust
> > DMA mapping resources (e.g. IOVA with an IOMMU or bounce-buffer slots
> > with SWIOTLB), leading to dma_map_* failures.
> 
> That looks like a horrible API. It pushes a requirement onto drivers to
> clean up something done by clients, and is completely undocumented.
> Can't those calls be moved somewhere in the DMA engine core ?

In general, I agree. No bandwidth for an API cleanup here, though. It
affects multiple drivers.