[PATCH v13 09/24] vfio: add container device assignment API

[Anatoly Burakov <anatoly.burakov@intel.com>]

Currently, VFIO has explicit group bind API's, but the way they're used is
such that no one actually cares about VFIO groups, and the real goal of
everyone using VFIO group bind API is to bind devices to particular VFIO
container, such that when `dev_vfio_setup_device` call eventually comes,
VFIO will pick up the correct container.

To remove dependency on group API's, add a new "container assign device"
API call that will do the same thing, but will not depend on managing VFIO
group fd's.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 lib/eal/freebsd/eal.c      | 10 ++++++++++
 lib/eal/include/dev_vfio.h | 26 ++++++++++++++++++++++++++
 lib/eal/linux/eal_vfio.c   | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/lib/eal/freebsd/eal.c b/lib/eal/freebsd/eal.c
index 2990cf14cd..0650abf406 100644
--- a/lib/eal/freebsd/eal.c
+++ b/lib/eal/freebsd/eal.c
@@ -950,3 +950,13 @@ dev_vfio_container_dma_unmap(__rte_unused int container_fd,
 	rte_errno = ENOTSUP;
 	return -1;
 }
+
+RTE_EXPORT_INTERNAL_SYMBOL(dev_vfio_container_assign_device)
+int
+dev_vfio_container_assign_device(__rte_unused int vfio_container_fd,
+		__rte_unused const char *sysfs_base,
+		__rte_unused const char *dev_addr)
+{
+	rte_errno = ENOTSUP;
+	return -1;
+}
diff --git a/lib/eal/include/dev_vfio.h b/lib/eal/include/dev_vfio.h
index 3719cc6adc..85b4dbd3fc 100644
--- a/lib/eal/include/dev_vfio.h
+++ b/lib/eal/include/dev_vfio.h
@@ -280,6 +280,32 @@ __rte_internal
 int
 dev_vfio_container_destroy(int container_fd);
 
+/**
+ * @internal
+ *
+ * Assign a device to a VFIO container.
+ *
+ * Doing so will cause `dev_vfio_setup_device()` call to set up the device with
+ * the VFIO container specified in this assign operation.
+ *
+ * This function is only relevant on Linux.
+ *
+ * @param vfio_container_fd
+ *   VFIO container file descriptor.
+ * @param sysfs_base
+ *   Sysfs path prefix.
+ * @param dev_addr
+ *   Device identifier.
+ *
+ * @return
+ *   0 on success.
+ *   <0 on failure.
+ */
+__rte_internal
+int
+dev_vfio_container_assign_device(int vfio_container_fd, const char *sysfs_base,
+		const char *dev_addr);
+
 /**
  * @internal
  * Bind a IOMMU group to a container.
diff --git a/lib/eal/linux/eal_vfio.c b/lib/eal/linux/eal_vfio.c
index a64173fe7f..29c03d01b4 100644
--- a/lib/eal/linux/eal_vfio.c
+++ b/lib/eal/linux/eal_vfio.c
@@ -2109,6 +2109,38 @@ dev_vfio_container_destroy(int container_fd)
 	return 0;
 }
 
+RTE_EXPORT_INTERNAL_SYMBOL(dev_vfio_container_assign_device)
+int
+dev_vfio_container_assign_device(int vfio_container_fd, const char *sysfs_base,
+		const char *dev_addr)
+{
+	int iommu_group_num;
+	int ret;
+
+	ret = dev_vfio_get_group_num(sysfs_base, dev_addr, &iommu_group_num);
+	if (ret < 0) {
+		EAL_LOG(ERR, "Cannot get IOMMU group number for device %s",
+			dev_addr);
+		return -1;
+	} else if (ret == 0) {
+		EAL_LOG(ERR,
+			"Device %s is not assigned to any IOMMU group",
+			dev_addr);
+		return -1;
+	}
+
+	ret = dev_vfio_container_group_bind(vfio_container_fd,
+			iommu_group_num);
+	if (ret < 0) {
+		EAL_LOG(ERR,
+			"Cannot bind IOMMU group %d for device %s",
+			iommu_group_num, dev_addr);
+		return -1;
+	}
+
+	return 0;
+}
+
 RTE_EXPORT_INTERNAL_SYMBOL(dev_vfio_container_group_bind)
 int
 dev_vfio_container_group_bind(int container_fd, int iommu_group_num)
-- 
2.52.0