Introduces a VFIO based AP device. The device is defined via
the QEMU command line by specifying:
-device vfio-ap,sysfsdev=<path-to-mediated-matrix-device>
There may be only one vfio-ap device configured for a guest.
The mediated matrix device is created by the VFIO AP device
driver by writing a UUID to a sysfs attribute file (see
docs/vfio-ap.txt). The mediated matrix device will be named
after the UUID. Symbolic links to the $uuid are created in
many places, so the path to the mediated matrix device $uuid
can be specified in any of the following ways:
/sys/devices/vfio_ap/matrix/$uuid
/sys/devices/vfio_ap/matrix/mdev_supported_types/vfio_ap-passthrough/devices/$uuid
/sys/bus/mdev/devices/$uuid
/sys/bus/mdev/drivers/vfio_mdev/$uuid
When the vfio-ap device is realized, it acquires and opens the
VFIO iommu group to which the mediated matrix device is
bound. This causes a VFIO group notification event to be
signaled. The vfio_ap device driver's group notification
handler will get called at which time the device driver
will configure the the AP devices to which the guest will
be granted access.
Signed-off-by: Tony Krowiak <address@hidden>
---
default-configs/s390x-softmmu.mak | 1 +
hw/vfio/Makefile.objs | 1 +
hw/vfio/ap.c | 191
+++++++++++++++++++++++++++++++++++++
include/hw/vfio/vfio-common.h | 1 +
4 files changed, 194 insertions(+), 0 deletions(-)
create mode 100644 hw/vfio/ap.c
+static void vfio_ap_realize(DeviceState *dev, Error **errp)
+{
+ VFIODevice *vbasedev;
+ VFIOGroup *vfio_group;
+ APDevice *apdev = DO_UPCAST(APDevice, parent_obj, dev);
+ char *mdevid;
+ Error *local_err = NULL;
+ int ret;
+
+ /*
+ * Since a guest's matrix is configured in its entirety by the mediated
+ * matrix device and hot plug is not currently supported, there is no
+ * need to have more than one vfio-ap device. Check if a vfio-ap device
+ * has already been defined.
+ */
+ if (vfio_apdev) {
+ error_setg(&local_err, "Only one %s device is allowed",
+ VFIO_AP_DEVICE_TYPE);
+ goto out_err;
+ }
+
+ if (!s390_has_feat(S390_FEAT_AP)) {
+ error_setg(&local_err, "AP support not enabled");
+ goto out_err;
+ }
+
+ vfio_apdev = DO_UPCAST(VFIOAPDevice, apdev, apdev);
+
+ vfio_group = vfio_ap_get_group(vfio_apdev, &local_err);
+ if (!vfio_group) {
+ goto out_err;
+ }
+
+ vfio_apdev->vdev.ops = &vfio_ap_ops;
+ vfio_apdev->vdev.type = VFIO_DEVICE_TYPE_AP;
+ mdevid = basename(vfio_apdev->vdev.sysfsdev);
+ vfio_apdev->vdev.name = g_strdup_printf("%s", mdevid);
+ vfio_apdev->vdev.dev = dev;
+ QLIST_FOREACH(vbasedev, &vfio_group->device_list, next) {
+ if (strcmp(vbasedev->name, vfio_apdev->vdev.name) == 0) {
+ error_setg(&local_err,
+ "%s: AP device %s has already been realized",
+ VFIO_AP_DEVICE_TYPE, vfio_apdev->vdev.name);
+ goto out_device_err;
+ }
+ }
+
+ ret = vfio_get_device(vfio_group, mdevid, &vfio_apdev->vdev, &local_err);
+ if (ret) {
+ goto out_device_err;
+ }