/* * QEMU vhost-user backend * * Copyright (C) 2018 Red Hat Inc * * Authors: * Marc-André Lureau <marcandre.lureau@redhat.com> * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. */ #include "qemu/osdep.h" #include "qapi/error.h" #include "qapi/qmp/qerror.h" #include "qemu/error-report.h" #include "qom/object_interfaces.h" #include "sysemu/vhost-user-backend.h" #include "sysemu/kvm.h" #include "io/channel-command.h" #include "hw/virtio/virtio-bus.h" static bool ioeventfd_enabled(void) { return kvm_enabled() && kvm_eventfds_enabled(); } int vhost_user_backend_dev_init(VhostUserBackend *b, VirtIODevice *vdev, unsigned nvqs, Error **errp) { int ret; assert(!b->vdev && vdev); if (!ioeventfd_enabled()) { error_setg(errp, "vhost initialization failed: requires kvm"); return -1; } if (!vhost_user_init(&b->vhost_user, &b->chr, errp)) { return -1; } b->vdev = vdev; b->dev.nvqs = nvqs; b->dev.vqs = g_new0(struct vhost_virtqueue, nvqs); ret = vhost_dev_init(&b->dev, &b->vhost_user, VHOST_BACKEND_TYPE_USER, 0); if (ret < 0) { error_setg_errno(errp, -ret, "vhost initialization failed"); return -1; } return 0; } void vhost_user_backend_start(VhostUserBackend *b) { BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev))); VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); int ret, i ; if (b->started) { return; } if (!k->set_guest_notifiers) { error_report("binding does not support guest notifiers"); return; } ret = vhost_dev_enable_notifiers(&b->dev, b->vdev); if (ret < 0) { return; } ret = k->set_guest_notifiers(qbus->parent, b->dev.nvqs, true); if (ret < 0) { error_report("Error binding guest notifier"); goto err_host_notifiers; } b->dev.acked_features = b->vdev->guest_features; ret = vhost_dev_start(&b->dev, b->vdev); if (ret < 0) { error_report("Error start vhost dev"); 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 < b->dev.nvqs; i++) { vhost_virtqueue_mask(&b->dev, b->vdev, b->dev.vq_index + i, false); } b->started = true; return; err_guest_notifiers: k->set_guest_notifiers(qbus->parent, b->dev.nvqs, false); err_host_notifiers: vhost_dev_disable_notifiers(&b->dev, b->vdev); } void vhost_user_backend_stop(VhostUserBackend *b) { BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev))); VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); int ret = 0; if (!b->started) { return; } vhost_dev_stop(&b->dev, b->vdev); if (k->set_guest_notifiers) { ret = k->set_guest_notifiers(qbus->parent, b->dev.nvqs, false); if (ret < 0) { error_report("vhost guest notifier cleanup failed: %d", ret); } } assert(ret >= 0); vhost_dev_disable_notifiers(&b->dev, b->vdev); b->started = false; } static void set_chardev(Object *obj, const char *value, Error **errp) { VhostUserBackend *b = VHOST_USER_BACKEND(obj); Chardev *chr; if (b->completed) { error_setg(errp, QERR_PERMISSION_DENIED); return; } g_free(b->chr_name); b->chr_name = g_strdup(value); chr = qemu_chr_find(b->chr_name); if (chr == NULL) { error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "Chardev '%s' not found", b->chr_name); return; } if (!qemu_chr_fe_init(&b->chr, chr, errp)) { return; } b->completed = true; /* could call vhost_dev_init() so early message can be exchanged */ } static char *get_chardev(Object *obj, Error **errp) { VhostUserBackend *b = VHOST_USER_BACKEND(obj); Chardev *chr = qemu_chr_fe_get_driver(&b->chr); if (chr && chr->label) { return g_strdup(chr->label); } return NULL; } static void vhost_user_backend_init(Object *obj) { object_property_add_str(obj, "chardev", get_chardev, set_chardev); } static void vhost_user_backend_finalize(Object *obj) { VhostUserBackend *b = VHOST_USER_BACKEND(obj); g_free(b->dev.vqs); g_free(b->chr_name); vhost_user_cleanup(&b->vhost_user); qemu_chr_fe_deinit(&b->chr, true); } static const TypeInfo vhost_user_backend_info = { .name = TYPE_VHOST_USER_BACKEND, .parent = TYPE_OBJECT, .instance_size = sizeof(VhostUserBackend), .instance_init = vhost_user_backend_init, .instance_finalize = vhost_user_backend_finalize, .class_size = sizeof(VhostUserBackendClass), }; static void register_types(void) { type_register_static(&vhost_user_backend_info); } type_init(register_types);