[Qemu-devel] [PATCH 2/3] vfio: add support for spapr platform (powerpc64 server)

[Alexey Kardashevskiy <aik@ozlabs.ru>]

The existing code assumes that containers are capable of
multiple groups support which is not the case for POWERPC64
where groups are defined by the hardware configuration and
cannot share one container.

The earlier proposal for PPC64 support was:
- spapr_phb_vfio_init(): create a spapr-pci-vfio-host-bridge,
	IOMMU ID is already known at this stage;
- spapr_pci_vfio_scan(): start scanning the group and adding devices;
- vfio_initfn(): the VFIO device init function allocates a group struct
	(if not yet);
- vfio_get_group():  a group struct allocator allocates a container
	(if not yet);
- vfio_connect_container(): connects a group to a container, requests
	POWERPC64 specific properties and calls a callback to spapr_pci.c
	passing those properties.

As the group ID is knows from the very beginning (as it is supplied via
the command line), it makes more sense to create group and container
structs first and then add devices from this group.

In order to achieve this, this patch adds a vfio_container_spapr_alloc()
function which allocates sPAPR container and returns its properties which
are a DMA window size and start.

Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 hw/misc/vfio.c         |   79 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/hw/misc/vfio.h |    3 ++
 2 files changed, 82 insertions(+)

diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
index 503125e..adcbb80 100644
--- a/hw/misc/vfio.c
+++ b/hw/misc/vfio.c
@@ -2684,6 +2684,85 @@ static int vfio_connect_container(VFIOGroup *group)
     return 0;
 }
 
+VFIOContainer *vfio_container_spapr_alloc(VFIOGroup *group,
+                                          struct vfio_iommu_spapr_tce_info *info)
+{
+    VFIOContainer *container;
+    int ret, fd;
+
+    if (group->container) {
+        return NULL;
+    }
+
+    fd = qemu_open("/dev/vfio/vfio", O_RDWR);
+    if (fd < 0) {
+        error_report("vfio: failed to open /dev/vfio/vfio: %m");
+        return NULL;
+    }
+
+    ret = ioctl(fd, VFIO_GET_API_VERSION);
+    if (ret != VFIO_API_VERSION) {
+        error_report("vfio: supported vfio version: %d, "
+                     "reported version: %d", VFIO_API_VERSION, ret);
+        close(fd);
+        return NULL;
+    }
+
+    container = g_malloc0(sizeof(*container));
+    container->fd = fd;
+
+    if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU)) {
+        ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
+        if (ret) {
+            error_report("vfio: failed to set group container: %s",
+                         strerror(errno));
+            g_free(container);
+            close(fd);
+            return NULL;
+        }
+
+        ret = ioctl(fd, VFIO_SET_IOMMU, VFIO_SPAPR_TCE_IOMMU);
+        if (ret) {
+            error_report("vfio: failed to set iommu for container: %s",
+                         strerror(errno));
+            g_free(container);
+            close(fd);
+            return NULL;
+        }
+
+        ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, info);
+        if (ret) {
+            error_report("vfio: failed to get iommu info for container: %s",
+                         strerror(errno));
+            g_free(container);
+            close(fd);
+            return NULL;
+        }
+
+        ret = ioctl(container->fd, VFIO_IOMMU_ENABLE);
+        if (ret) {
+            error_report("vfio: failed to enable container: %s",
+                         strerror(errno));
+            g_free(container);
+            close(fd);
+            return NULL;
+        }
+    } else {
+        error_report("vfio: No available IOMMU models");
+        g_free(container);
+        close(fd);
+        return NULL;
+    }
+
+    QLIST_INIT(&container->group_list);
+    QLIST_INSERT_HEAD(&container_list, container, next);
+
+    group->container = container;
+    QLIST_INSERT_HEAD(&container->group_list, group, container_next);
+
+    return container;
+}
+
 static void vfio_disconnect_container(VFIOGroup *group)
 {
     VFIOContainer *container = group->container;
diff --git a/include/hw/misc/vfio.h b/include/hw/misc/vfio.h
index f39aef8..d1c7ff1 100644
--- a/include/hw/misc/vfio.h
+++ b/include/hw/misc/vfio.h
@@ -14,4 +14,7 @@ extern int vfio_dma_map(struct VFIOContainer *container, hwaddr iova,
 
 extern struct VFIOGroup *vfio_get_group(int groupid, bool connect);
 
+extern struct VFIOContainer *vfio_container_spapr_alloc(struct VFIOGroup *group,
+                                                        struct vfio_iommu_spapr_tce_info *info);
+
 #endif
-- 
1.7.10.4