[RFC PATCH 2/6] bus/cdx: add dma map and unmap support

[Nipun Gupta]

CDX bus can use VFIO interface for mapping and unmapping
of DMA addresses in the IOMMU. This change adds the callback
support for map and unmap APIs as well as fetching the IOMMU
class.

Signed-off-by: Nipun Gupta <nipun.gupta at amd.com>
---
 drivers/bus/cdx/cdx.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/drivers/bus/cdx/cdx.c b/drivers/bus/cdx/cdx.c
index 4c85c5dc01..cb04639b0d 100644
--- a/drivers/bus/cdx/cdx.c
+++ b/drivers/bus/cdx/cdx.c
@@ -549,12 +549,52 @@ cdx_find_device(const struct rte_device *start, rte_dev_cmp_t cmp,
 	return NULL;
 }
 
+static int
+cdx_dma_map(struct rte_device *dev, void *addr, uint64_t iova, size_t len)
+{
+	struct rte_cdx_device *cdx_dev = RTE_DEV_TO_CDX_DEV(dev);
+
+	if (!cdx_dev) {
+		rte_errno = EINVAL;
+		return -1;
+	}
+
+	return rte_vfio_container_dma_map(RTE_VFIO_DEFAULT_CONTAINER_FD,
+					  (uintptr_t)addr, iova, len);
+}
+
+static int
+cdx_dma_unmap(struct rte_device *dev, void *addr, uint64_t iova, size_t len)
+{
+	struct rte_cdx_device *cdx_dev = RTE_DEV_TO_CDX_DEV(dev);
+
+	if (!cdx_dev) {
+		rte_errno = EINVAL;
+		return -1;
+	}
+
+	return rte_vfio_container_dma_unmap(RTE_VFIO_DEFAULT_CONTAINER_FD,
+					    (uintptr_t)addr, iova, len);
+}
+
+static enum rte_iova_mode
+rte_cdx_get_iommu_class(void)
+{
+	if (TAILQ_EMPTY(&rte_cdx_bus.device_list))
+		return RTE_IOVA_DC;
+
+	return RTE_IOVA_VA;
+}
+
 struct rte_cdx_bus rte_cdx_bus = {
 	.bus = {
 		.scan = rte_cdx_scan,
 		.probe = cdx_probe,
 		.find_device = cdx_find_device,
 		.parse = cdx_parse,
+		.dma_map = cdx_dma_map,
+		.dma_unmap = cdx_dma_unmap,
+		.get_iommu_class = rte_cdx_get_iommu_class,
 	},
 	.device_list = TAILQ_HEAD_INITIALIZER(rte_cdx_bus.device_list),
 	.driver_list = TAILQ_HEAD_INITIALIZER(rte_cdx_bus.driver_list),
-- 
2.25.1