On 2022-04-02 15:34:55 +0200, Sven Peter wrote: > > > On Tue, Mar 22, 2022, at 14:38, Arnd Bergmann wrote: > > On Mon, Mar 21, 2022 at 5:50 PM Sven Peter <sven@xxxxxxxxxxxxx> wrote: > > > >> +static int apple_nvme_sart_dma_setup(void *cookie, struct apple_rtkit_shmem *bfr, > >> + dma_addr_t iova, size_t size) > >> +{ > >> + struct apple_nvme *anv = cookie; > >> + int ret; > >> + > >> + if (iova) > >> + return -EINVAL; > >> + > >> + bfr->buffer = dma_alloc_coherent(anv->dev, size, &iova, GFP_KERNEL); > >> + if (!bfr->buffer) > >> + return -ENOMEM; > > > > You pass 'iova' as an argument, but then replace it with the address > > returned by dma_alloc_coherent(). Can you remove the function > > argument? > > Yup, will remove it. You can remove it but we will have to add it back once we submit the dcp driver (display co-processor). dcp is initialized during boot and uses a single pre-allocated buffer which needs to be mapped instead of allocated. It seemed easier to make apple_rtkit_ops.shmem_setup() omnipotent than adding a different function pointer for this case. Janne