@@ -343,11 +343,15 @@ static int iommufd_attach_device(char *name, VFIODevice *vbasedev,
uint32_t ioas_id;
Error *err = NULL;
- devfd = vfio_get_devicefd(vbasedev->sysfsdev, errp);
- if (devfd < 0) {
- return devfd;
+ if (vbasedev->fd < 0) {
+ devfd = vfio_get_devicefd(vbasedev->sysfsdev, errp);
+ if (devfd < 0) {
+ return devfd;
+ }
+ vbasedev->fd = devfd;
+ } else {
+ devfd = vbasedev->fd;
}
- vbasedev->fd = devfd;
space = vfio_get_address_space(as);
@@ -44,6 +44,7 @@
#include "migration/qemu-file.h"
#include "linux/iommufd.h"
#include "sysemu/iommufd.h"
+#include "monitor/monitor.h"
#define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug"
@@ -3185,12 +3186,18 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
}
#endif
- if (!vbasedev->sysfsdev) {
+ if (vbasedev->fd < 0 && !vbasedev->sysfsdev) {
if (!(~vdev->host.domain || ~vdev->host.bus ||
~vdev->host.slot || ~vdev->host.function)) {
error_setg(errp, "No provided host device");
+#ifdef CONFIG_IOMMUFD
+ error_append_hint(errp, "Use -device vfio-pci,host=DDDD:BB:DD.F, "
+ "-device vfio-pci,sysfsdev=PATH_TO_DEVICE "
+ "or -device vfio-pci,fd=DEVICE_FD\n");
+#else
error_append_hint(errp, "Use -device vfio-pci,host=DDDD:BB:DD.F "
"or -device vfio-pci,sysfsdev=PATH_TO_DEVICE\n");
+#endif
return;
}
vbasedev->sysfsdev =
@@ -3199,13 +3206,28 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
vdev->host.slot, vdev->host.function);
}
- if (stat(vbasedev->sysfsdev, &st) < 0) {
- error_setg_errno(errp, errno, "no such host device");
- error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev);
- return;
+ if (vbasedev->fd < 0) {
+ if (stat(vbasedev->sysfsdev, &st) < 0) {
+ error_setg_errno(errp, errno, "no such host device");
+ error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev);
+ return;
+ }
+ vbasedev->name = g_path_get_basename(vbasedev->sysfsdev);
+ }
+#ifdef CONFIG_IOMMUFD
+ else {
+ if (!vbasedev->iommufd) {
+ error_setg(errp, "Use FD passing only with iommufd backend");
+ return;
+ }
+ /*
+ * Give a name with fd so any function printing out vbasedev->name
+ * will not break.
+ */
+ vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd);
}
+#endif
- vbasedev->name = g_path_get_basename(vbasedev->sysfsdev);
vbasedev->ops = &vfio_pci_ops;
vbasedev->type = VFIO_DEVICE_TYPE_PCI;
vbasedev->dev = DEVICE(vdev);
@@ -3574,6 +3596,7 @@ static void vfio_instance_init(Object *obj)
vdev->host.bus = ~0U;
vdev->host.slot = ~0U;
vdev->host.function = ~0U;
+ vdev->vbasedev.fd = -1;
vdev->nv_gpudirect_clique = 0xFF;
@@ -3634,6 +3657,21 @@ static Property vfio_pci_dev_properties[] = {
DEFINE_PROP_END_OF_LIST(),
};
+#ifdef CONFIG_IOMMUFD
+static void vfio_pci_set_fd(Object *obj, const char *str, Error **errp)
+{
+ VFIOPCIDevice *vdev = VFIO_PCI(obj);
+ int fd = -1;
+
+ fd = monitor_fd_param(monitor_cur(), str, errp);
+ if (fd == -1) {
+ error_prepend(errp, "Could not parse remote object fd %s:", str);
+ return;
+ }
+ vdev->vbasedev.fd = fd;
+}
+#endif
+
static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
@@ -3641,6 +3679,9 @@ static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
dc->reset = vfio_pci_reset;
device_class_set_props(dc, vfio_pci_dev_properties);
+#ifdef CONFIG_IOMMUFD
+ object_class_property_add_str(klass, "fd", NULL, vfio_pci_set_fd);
+#endif
dc->desc = "VFIO-based PCI device assignment";
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
pdc->realize = vfio_realize;
This gives management tools like libvirt a chance to open the vfio cdev with privilege and pass FD to qemu. This way qemu never needs to have privilege to open a VFIO or iommu cdev node. There is no easy way to check if a device is mdev with FD passing, so fail the x-balloon-allowed check unconditionally in this case. There is also no easy way to get BDF as name with FD passing, so we fake a name by VFIO_FD[fd]. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> --- hw/vfio/iommufd.c | 12 +++++++---- hw/vfio/pci.c | 53 +++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 55 insertions(+), 10 deletions(-)