On 3/5/26 8:14 PM, Koichiro Den wrote:
> When vNTB is used as a PCI endpoint function, the NTB device is backed
> by a virtual PCI function. For DMA API allocations and mappings, NTB
> clients must use the device that is associated with the IOMMU domain.
>
> Implement ntb_dev_ops->get_dma_dev() for pci-epf-vntb and return the EPC
> parent device.
>
> Suggested-by: Frank Li <Frank.Li@nxp.com>
> Signed-off-by: Koichiro Den <den@valinux.co.jp>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
> drivers/pci/endpoint/functions/pci-epf-vntb.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 20a400e83439..e5433404f573 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -1436,6 +1436,14 @@ static int vntb_epf_link_disable(struct ntb_dev *ntb)
> return 0;
> }
>
> +static struct device *vntb_epf_get_dma_dev(struct ntb_dev *ndev)
> +{
> + struct epf_ntb *ntb = ntb_ndev(ndev);
> + struct pci_epc *epc = ntb->epf->epc;
> +
> + return epc->dev.parent;
> +}
> +
> static const struct ntb_dev_ops vntb_epf_ops = {
> .mw_count = vntb_epf_mw_count,
> .spad_count = vntb_epf_spad_count,
> @@ -1457,6 +1465,7 @@ static const struct ntb_dev_ops vntb_epf_ops = {
> .db_clear_mask = vntb_epf_db_clear_mask,
> .db_clear = vntb_epf_db_clear,
> .link_disable = vntb_epf_link_disable,
> + .get_dma_dev = vntb_epf_get_dma_dev,
> };
>
> static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)