[dpdk-dev] [PATCH v2 1/6] vfio: allow DMA map of memory for the default vfio fd

[Shahaf Shuler <shahafs@mellanox.com>]

Enable users the option to call rte_vfio_dma_map with request to map
to the default vfio fd.

Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
---
 doc/guides/rel_notes/release_19_05.rst   |  3 +++
 lib/librte_eal/common/include/rte_vfio.h |  8 ++++++--
 lib/librte_eal/linuxapp/eal/eal_vfio.c   | 10 ++++++++--
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/doc/guides/rel_notes/release_19_05.rst b/doc/guides/rel_notes/release_19_05.rst
index 2b0f60d3d8..2c682e36cf 100644
--- a/doc/guides/rel_notes/release_19_05.rst
+++ b/doc/guides/rel_notes/release_19_05.rst
@@ -110,6 +110,9 @@ ABI Changes
    Also, make sure to start the actual text at the margin.
    =========================================================
 
+* vfio: Functions ``rte_vfio_container_dma_map`` and
+  ``rte_vfio_container_dma_unmap`` have been extended with an option to
+  request mapping or un-mapping to the default vfio container fd.
 
 Shared Library Versions
 -----------------------
diff --git a/lib/librte_eal/common/include/rte_vfio.h b/lib/librte_eal/common/include/rte_vfio.h
index cae96fab90..54a0df5726 100644
--- a/lib/librte_eal/common/include/rte_vfio.h
+++ b/lib/librte_eal/common/include/rte_vfio.h
@@ -73,6 +73,8 @@ struct vfio_info_cap_header {
 #define RTE_VFIO_CAP_MSIX_MAPPABLE 3
 #endif
 
+#define RTE_VFIO_DEFAULT_CONTAINER_FD (-1)
+
 #else /* not VFIO_PRESENT */
 
 /* we don't need an actual definition, only pointer is used */
@@ -347,7 +349,8 @@ rte_vfio_container_group_unbind(int container_fd, int iommu_group_num);
  * Perform DMA mapping for devices in a container.
  *
  * @param container_fd
- *   the specified container fd
+ *   the specified container fd. Use RTE_VFIO_DEFAULT_CONTAINER_FD to
+ *   use the default container.
  *
  * @param vaddr
  *   Starting virtual address of memory to be mapped.
@@ -370,7 +373,8 @@ rte_vfio_container_dma_map(int container_fd, uint64_t vaddr,
  * Perform DMA unmapping for devices in a container.
  *
  * @param container_fd
- *   the specified container fd
+ *   the specified container fd. Use RTE_VFIO_DEFAULT_CONTAINER_FD to
+ *   use the default container.
  *
  * @param vaddr
  *   Starting virtual address of memory to be unmapped.
diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c
index c821e83826..9adbda8bb7 100644
--- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
+++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
@@ -1897,7 +1897,10 @@ rte_vfio_container_dma_map(int container_fd, uint64_t vaddr, uint64_t iova,
 		return -1;
 	}
 
-	vfio_cfg = get_vfio_cfg_by_container_fd(container_fd);
+	if (container_fd == RTE_VFIO_DEFAULT_CONTAINER_FD)
+		vfio_cfg = default_vfio_cfg;
+	else
+		vfio_cfg = get_vfio_cfg_by_container_fd(container_fd);
 	if (vfio_cfg == NULL) {
 		RTE_LOG(ERR, EAL, "Invalid container fd\n");
 		return -1;
@@ -1917,7 +1920,10 @@ rte_vfio_container_dma_unmap(int container_fd, uint64_t vaddr, uint64_t iova,
 		return -1;
 	}
 
-	vfio_cfg = get_vfio_cfg_by_container_fd(container_fd);
+	if (container_fd == RTE_VFIO_DEFAULT_CONTAINER_FD)
+		vfio_cfg = default_vfio_cfg;
+	else
+		vfio_cfg = get_vfio_cfg_by_container_fd(container_fd);
 	if (vfio_cfg == NULL) {
 		RTE_LOG(ERR, EAL, "Invalid container fd\n");
 		return -1;
-- 
2.12.0