diff options
Diffstat (limited to 'hw/virtio/vhost-user-scmi.c')
| -rw-r--r-- | hw/virtio/vhost-user-scmi.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/hw/virtio/vhost-user-scmi.c b/hw/virtio/vhost-user-scmi.c new file mode 100644 index 0000000000..d386fb2df9 --- /dev/null +++ b/hw/virtio/vhost-user-scmi.c @@ -0,0 +1,306 @@ +/* + * Vhost-user SCMI virtio device + * + * SPDX-FileCopyrightText: Red Hat, Inc. + * SPDX-License-Identifier: GPL-2.0-or-later + * + * Implementation based on other vhost-user devices in QEMU. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/error-report.h" +#include "hw/virtio/virtio-bus.h" +#include "hw/virtio/vhost-user-scmi.h" +#include "standard-headers/linux/virtio_ids.h" +#include "standard-headers/linux/virtio_scmi.h" +#include "trace.h" + +/* + * In this version, we don't support VIRTIO_SCMI_F_SHARED_MEMORY. + * Note that VIRTIO_SCMI_F_SHARED_MEMORY is currently not supported in + * Linux VirtIO SCMI guest driver. + */ +static const int feature_bits[] = { + VIRTIO_F_VERSION_1, + VIRTIO_F_NOTIFY_ON_EMPTY, + VIRTIO_RING_F_INDIRECT_DESC, + VIRTIO_RING_F_EVENT_IDX, + VIRTIO_F_RING_RESET, + VIRTIO_SCMI_F_P2A_CHANNELS, + VHOST_INVALID_FEATURE_BIT +}; + +static int vu_scmi_start(VirtIODevice *vdev) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + struct vhost_dev *vhost_dev = &scmi->vhost_dev; + int ret, i; + + if (!k->set_guest_notifiers) { + error_report("binding does not support guest notifiers"); + return -ENOSYS; + } + + ret = vhost_dev_enable_notifiers(vhost_dev, vdev); + if (ret < 0) { + error_report("Error enabling host notifiers: %d", ret); + return ret; + } + + ret = k->set_guest_notifiers(qbus->parent, vhost_dev->nvqs, true); + if (ret < 0) { + error_report("Error binding guest notifier: %d", ret); + goto err_host_notifiers; + } + + vhost_ack_features(&scmi->vhost_dev, feature_bits, vdev->guest_features); + + ret = vhost_dev_start(&scmi->vhost_dev, vdev, true); + if (ret < 0) { + error_report("Error starting vhost-user-scmi: %d", ret); + goto err_guest_notifiers; + } + + /* + * guest_notifier_mask/pending not used yet, so just unmask + * everything here. virtio-pci will do the right thing by + * enabling/disabling irqfd. + */ + for (i = 0; i < scmi->vhost_dev.nvqs; i++) { + vhost_virtqueue_mask(&scmi->vhost_dev, vdev, i, false); + } + return 0; + +err_guest_notifiers: + k->set_guest_notifiers(qbus->parent, vhost_dev->nvqs, false); +err_host_notifiers: + vhost_dev_disable_notifiers(vhost_dev, vdev); + + return ret; +} + +static void vu_scmi_stop(VirtIODevice *vdev) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + struct vhost_dev *vhost_dev = &scmi->vhost_dev; + int ret; + + if (!k->set_guest_notifiers) { + return; + } + + vhost_dev_stop(vhost_dev, vdev, true); + + ret = k->set_guest_notifiers(qbus->parent, vhost_dev->nvqs, false); + if (ret < 0) { + error_report("vhost guest notifier cleanup failed: %d", ret); + return; + } + vhost_dev_disable_notifiers(vhost_dev, vdev); +} + +static void vu_scmi_set_status(VirtIODevice *vdev, uint8_t status) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + bool should_start = virtio_device_should_start(vdev, status); + + if (!scmi->connected) { + return; + } + if (vhost_dev_is_started(&scmi->vhost_dev) == should_start) { + return; + } + + if (should_start) { + vu_scmi_start(vdev); + } else { + vu_scmi_stop(vdev); + } +} + +static uint64_t vu_scmi_get_features(VirtIODevice *vdev, uint64_t features, + Error **errp) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + + return vhost_get_features(&scmi->vhost_dev, feature_bits, features); +} + +static void vu_scmi_handle_output(VirtIODevice *vdev, VirtQueue *vq) +{ + /* + * Not normally called; it's the daemon that handles the queue; + * however virtio's cleanup path can call this. + */ +} + +static void vu_scmi_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + + if (idx == VIRTIO_CONFIG_IRQ_IDX) { + return; + } + + vhost_virtqueue_mask(&scmi->vhost_dev, vdev, idx, mask); +} + +static bool vu_scmi_guest_notifier_pending(VirtIODevice *vdev, int idx) +{ + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + + return vhost_virtqueue_pending(&scmi->vhost_dev, idx); +} + +static void vu_scmi_connect(DeviceState *dev) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + + if (scmi->connected) { + return; + } + scmi->connected = true; + + /* restore vhost state */ + if (virtio_device_started(vdev, vdev->status)) { + vu_scmi_start(vdev); + } +} + +static void vu_scmi_disconnect(DeviceState *dev) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCMI *scmi = VHOST_USER_SCMI(vdev); + + if (!scmi->connected) { + return; + } + scmi->connected = false; + + if (vhost_dev_is_started(&scmi->vhost_dev)) { + vu_scmi_stop(vdev); + } +} + +static void vu_scmi_event(void *opaque, QEMUChrEvent event) +{ + DeviceState *dev = opaque; + + switch (event) { + case CHR_EVENT_OPENED: + vu_scmi_connect(dev); + break; + case CHR_EVENT_CLOSED: + vu_scmi_disconnect(dev); + break; + case CHR_EVENT_BREAK: + case CHR_EVENT_MUX_IN: + case CHR_EVENT_MUX_OUT: + /* Ignore */ + break; + } +} + +static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserSCMI *scmi) +{ + virtio_delete_queue(scmi->cmd_vq); + virtio_delete_queue(scmi->event_vq); + g_free(scmi->vhost_dev.vqs); + virtio_cleanup(vdev); + vhost_user_cleanup(&scmi->vhost_user); +} + +static void vu_scmi_device_realize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCMI *scmi = VHOST_USER_SCMI(dev); + int ret; + + if (!scmi->chardev.chr) { + error_setg(errp, "vhost-user-scmi: chardev is mandatory"); + return; + } + + vdev->host_features |= (1ULL << VIRTIO_SCMI_F_P2A_CHANNELS); + + if (!vhost_user_init(&scmi->vhost_user, &scmi->chardev, errp)) { + return; + } + + virtio_init(vdev, VIRTIO_ID_SCMI, 0); + + scmi->cmd_vq = virtio_add_queue(vdev, 256, vu_scmi_handle_output); + scmi->event_vq = virtio_add_queue(vdev, 256, vu_scmi_handle_output); + scmi->vhost_dev.nvqs = 2; + scmi->vhost_dev.vqs = g_new0(struct vhost_virtqueue, scmi->vhost_dev.nvqs); + + ret = vhost_dev_init(&scmi->vhost_dev, &scmi->vhost_user, + VHOST_BACKEND_TYPE_USER, 0, errp); + if (ret < 0) { + error_setg_errno(errp, -ret, + "vhost-user-scmi: vhost_dev_init() failed"); + do_vhost_user_cleanup(vdev, scmi); + return; + } + + qemu_chr_fe_set_handlers(&scmi->chardev, NULL, NULL, vu_scmi_event, NULL, + dev, NULL, true); + + return; +} + +static void vu_scmi_device_unrealize(DeviceState *dev) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCMI *scmi = VHOST_USER_SCMI(dev); + + vu_scmi_set_status(vdev, 0); + vhost_dev_cleanup(&scmi->vhost_dev); + do_vhost_user_cleanup(vdev, scmi); +} + +static const VMStateDescription vu_scmi_vmstate = { + .name = "vhost-user-scmi", + .unmigratable = 1, +}; + +static Property vu_scmi_properties[] = { + DEFINE_PROP_CHR("chardev", VHostUserSCMI, chardev), + DEFINE_PROP_END_OF_LIST(), +}; + +static void vu_scmi_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); + + device_class_set_props(dc, vu_scmi_properties); + dc->vmsd = &vu_scmi_vmstate; + set_bit(DEVICE_CATEGORY_INPUT, dc->categories); + vdc->realize = vu_scmi_device_realize; + vdc->unrealize = vu_scmi_device_unrealize; + vdc->get_features = vu_scmi_get_features; + vdc->set_status = vu_scmi_set_status; + vdc->guest_notifier_mask = vu_scmi_guest_notifier_mask; + vdc->guest_notifier_pending = vu_scmi_guest_notifier_pending; +} + +static const TypeInfo vu_scmi_info = { + .name = TYPE_VHOST_USER_SCMI, + .parent = TYPE_VIRTIO_DEVICE, + .instance_size = sizeof(VHostUserSCMI), + .class_init = vu_scmi_class_init, +}; + +static void vu_scmi_register_types(void) +{ + type_register_static(&vu_scmi_info); +} + +type_init(vu_scmi_register_types) |