Expose a few low-level helper routings for setting up vfio_pci_device
structs. These routines will be used in a subsequent commit to assert
that VFIO_GROUP_GET_DEVICE_FD fails under certain conditions.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 .../lib/include/libvfio/vfio_pci_device.h     |  5 +++
 .../selftests/vfio/lib/vfio_pci_device.c      | 33 +++++++++++++------
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
index 896dfde88118..2389c7698335 100644
--- a/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
+++ b/tools/testing/selftests/vfio/lib/include/libvfio/vfio_pci_device.h
@@ -125,4 +125,9 @@ static inline bool vfio_pci_device_match(struct vfio_pci_device *device,
 
 const char *vfio_pci_get_cdev_path(const char *bdf);
 
+/* Low-level routines for setting up a struct vfio_pci_device */
+struct vfio_pci_device *vfio_pci_device_alloc(const char *bdf, struct iommu *iommu);
+void vfio_pci_group_setup(struct vfio_pci_device *device);
+void vfio_pci_iommu_setup(struct vfio_pci_device *device);
+
 #endif /* SELFTESTS_VFIO_LIB_INCLUDE_LIBVFIO_VFIO_PCI_DEVICE_H */
diff --git a/tools/testing/selftests/vfio/lib/vfio_pci_device.c b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
index e9423dc3864a..c1a3886dee30 100644
--- a/tools/testing/selftests/vfio/lib/vfio_pci_device.c
+++ b/tools/testing/selftests/vfio/lib/vfio_pci_device.c
@@ -199,7 +199,7 @@ static unsigned int vfio_pci_get_group_from_dev(const char *bdf)
 	return group;
 }
 
-static void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf)
+void vfio_pci_group_setup(struct vfio_pci_device *device)
 {
 	struct vfio_group_status group_status = {
 		.argsz = sizeof(group_status),
@@ -207,7 +207,7 @@ static void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf
 	char group_path[32];
 	int group;
 
-	group = vfio_pci_get_group_from_dev(bdf);
+	group = vfio_pci_get_group_from_dev(device->bdf);
 	snprintf(group_path, sizeof(group_path), "/dev/vfio/%d", group);
 
 	device->group_fd = open(group_path, O_RDWR);
@@ -219,14 +219,12 @@ static void vfio_pci_group_setup(struct vfio_pci_device *device, const char *bdf
 	ioctl_assert(device->group_fd, VFIO_GROUP_SET_CONTAINER, &device->iommu->container_fd);
 }
 
-static void vfio_pci_container_setup(struct vfio_pci_device *device, const char *bdf)
+void vfio_pci_iommu_setup(struct vfio_pci_device *device)
 {
 	struct iommu *iommu = device->iommu;
 	unsigned long iommu_type = iommu->mode->iommu_type;
 	int ret;
 
-	vfio_pci_group_setup(device, bdf);
-
 	ret = ioctl(iommu->container_fd, VFIO_CHECK_EXTENSION, iommu_type);
 	VFIO_ASSERT_GT(ret, 0, "VFIO IOMMU type %lu not supported\n", iommu_type);
 
@@ -236,8 +234,14 @@ static void vfio_pci_container_setup(struct vfio_pci_device *device, const char
 	 * because the IOMMU type is already set.
 	 */
 	(void)ioctl(iommu->container_fd, VFIO_SET_IOMMU, (void *)iommu_type);
+}
 
-	device->fd = ioctl(device->group_fd, VFIO_GROUP_GET_DEVICE_FD, bdf);
+static void vfio_pci_container_setup(struct vfio_pci_device *device)
+{
+	vfio_pci_group_setup(device);
+	vfio_pci_iommu_setup(device);
+
+	device->fd = ioctl(device->group_fd, VFIO_GROUP_GET_DEVICE_FD, device->bdf);
 	VFIO_ASSERT_GE(device->fd, 0);
 }
 
@@ -337,9 +341,7 @@ static void vfio_pci_iommufd_setup(struct vfio_pci_device *device,
 	vfio_device_attach_iommufd_pt(device->fd, device->iommu->ioas_id);
 }
 
-struct vfio_pci_device *__vfio_pci_device_init(const char *bdf,
-					       struct iommu *iommu,
-					       int device_fd)
+struct vfio_pci_device *vfio_pci_device_alloc(const char *bdf, struct iommu *iommu)
 {
 	struct vfio_pci_device *device;
 
@@ -349,9 +351,20 @@ struct vfio_pci_device *__vfio_pci_device_init(const char *bdf,
 	device->bdf = bdf;
 	device->iommu = iommu;
 
+	return device;
+}
+
+struct vfio_pci_device *__vfio_pci_device_init(const char *bdf,
+					       struct iommu *iommu,
+					       int device_fd)
+{
+	struct vfio_pci_device *device;
+
+	device = vfio_pci_device_alloc(bdf, iommu);
+
 	if (device->iommu->mode->container_path) {
 		VFIO_ASSERT_EQ(device_fd, -1);
-		vfio_pci_container_setup(device, bdf);
+		vfio_pci_container_setup(device);
 	} else {
 		vfio_pci_iommufd_setup(device, bdf, device_fd);
 	}
-- 
2.52.0.487.g5c8c507ade-goog