qemu

ap.c (4863B)

---

 /*
  * VFIO based AP matrix device assignment
  *
  * Copyright 2018 IBM Corp.
  * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
  *            Halil Pasic <pasic@linux.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or (at
  * your option) any later version. See the COPYING file in the top-level
  * directory.
  */
 
 #include "qemu/osdep.h"
 #include <linux/vfio.h>
 #include <sys/ioctl.h>
 #include "qapi/error.h"
 #include "hw/vfio/vfio.h"
 #include "hw/vfio/vfio-common.h"
 #include "hw/s390x/ap-device.h"
 #include "qemu/error-report.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "qemu/config-file.h"
 #include "kvm/kvm_s390x.h"
 #include "migration/vmstate.h"
 #include "hw/qdev-properties.h"
 #include "hw/s390x/ap-bridge.h"
 #include "exec/address-spaces.h"
 #include "qom/object.h"
 
 #define TYPE_VFIO_AP_DEVICE      "vfio-ap"
 
 struct VFIOAPDevice {
     APDevice apdev;
     VFIODevice vdev;
 };
 
 OBJECT_DECLARE_SIMPLE_TYPE(VFIOAPDevice, VFIO_AP_DEVICE)
 
 static void vfio_ap_compute_needs_reset(VFIODevice *vdev)
 {
     vdev->needs_reset = false;
 }
 
 /*
  * We don't need vfio_hot_reset_multi and vfio_eoi operations for
  * vfio-ap device now.
  */
 struct VFIODeviceOps vfio_ap_ops = {
     .vfio_compute_needs_reset = vfio_ap_compute_needs_reset,
 };
 
 static void vfio_ap_put_device(VFIOAPDevice *vapdev)
 {
     g_free(vapdev->vdev.name);
     vfio_put_base_device(&vapdev->vdev);
 }
 
 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp)
 {
     GError *gerror = NULL;
     char *symlink, *group_path;
     int groupid;
 
     symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev);
     group_path = g_file_read_link(symlink, &gerror);
     g_free(symlink);
 
     if (!group_path) {
         error_setg(errp, "%s: no iommu_group found for %s: %s",
                    TYPE_VFIO_AP_DEVICE, vapdev->vdev.sysfsdev, gerror->message);
         g_error_free(gerror);
         return NULL;
     }
 
     if (sscanf(basename(group_path), "%d", &groupid) != 1) {
         error_setg(errp, "vfio: failed to read %s", group_path);
         g_free(group_path);
         return NULL;
     }
 
     g_free(group_path);
 
     return vfio_get_group(groupid, &address_space_memory, errp);
 }
 
 static void vfio_ap_realize(DeviceState *dev, Error **errp)
 {
     int ret;
     char *mdevid;
     VFIOGroup *vfio_group;
     APDevice *apdev = AP_DEVICE(dev);
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
 
     vfio_group = vfio_ap_get_group(vapdev, errp);
     if (!vfio_group) {
         return;
     }
 
     vapdev->vdev.ops = &vfio_ap_ops;
     vapdev->vdev.type = VFIO_DEVICE_TYPE_AP;
     mdevid = basename(vapdev->vdev.sysfsdev);
     vapdev->vdev.name = g_strdup_printf("%s", mdevid);
     vapdev->vdev.dev = dev;
 
     /*
      * vfio-ap devices operate in a way compatible with discarding of
      * memory in RAM blocks, as no pages are pinned in the host.
      * This needs to be set before vfio_get_device() for vfio common to
      * handle ram_block_discard_disable().
      */
     vapdev->vdev.ram_block_discard_allowed = true;
 
     ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp);
     if (ret) {
         goto out_get_dev_err;
     }
 
     return;
 
 out_get_dev_err:
     vfio_ap_put_device(vapdev);
     vfio_put_group(vfio_group);
 }
 
 static void vfio_ap_unrealize(DeviceState *dev)
 {
     APDevice *apdev = AP_DEVICE(dev);
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
     VFIOGroup *group = vapdev->vdev.group;
 
     vfio_ap_put_device(vapdev);
     vfio_put_group(group);
 }
 
 static Property vfio_ap_properties[] = {
     DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev),
     DEFINE_PROP_END_OF_LIST(),
 };
 
 static void vfio_ap_reset(DeviceState *dev)
 {
     int ret;
     APDevice *apdev = AP_DEVICE(dev);
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
 
     ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET);
     if (ret) {
         error_report("%s: failed to reset %s device: %s", __func__,
                      vapdev->vdev.name, strerror(errno));
     }
 }
 
 static const VMStateDescription vfio_ap_vmstate = {
     .name = "vfio-ap",
     .unmigratable = 1,
 };
 
 static void vfio_ap_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     device_class_set_props(dc, vfio_ap_properties);
     dc->vmsd = &vfio_ap_vmstate;
     dc->desc = "VFIO-based AP device assignment";
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
     dc->realize = vfio_ap_realize;
     dc->unrealize = vfio_ap_unrealize;
     dc->hotpluggable = true;
     dc->reset = vfio_ap_reset;
     dc->bus_type = TYPE_AP_BUS;
 }
 
 static const TypeInfo vfio_ap_info = {
     .name = TYPE_VFIO_AP_DEVICE,
     .parent = TYPE_AP_DEVICE,
     .instance_size = sizeof(VFIOAPDevice),
     .class_init = vfio_ap_class_init,
 };
 
 static void vfio_ap_type_init(void)
 {
     type_register_static(&vfio_ap_info);
 }
 
 type_init(vfio_ap_type_init)