1 /* 2 * Virtio vsock device 3 * 4 * Copyright 2015 Red Hat, Inc. 5 * 6 * Authors: 7 * Stefan Hajnoczi <stefanha@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or 10 * (at your option) any later version. See the COPYING file in the 11 * top-level directory. 12 */ 13 14 #include "qemu/osdep.h" 15 #include "standard-headers/linux/virtio_vsock.h" 16 #include "qapi/error.h" 17 #include "hw/virtio/virtio-access.h" 18 #include "qemu/error-report.h" 19 #include "hw/qdev-properties.h" 20 #include "hw/virtio/vhost-vsock.h" 21 #include "monitor/monitor.h" 22 23 static void vhost_vsock_get_config(VirtIODevice *vdev, uint8_t *config) 24 { 25 VHostVSock *vsock = VHOST_VSOCK(vdev); 26 struct virtio_vsock_config vsockcfg = {}; 27 28 virtio_stq_p(vdev, &vsockcfg.guest_cid, vsock->conf.guest_cid); 29 memcpy(config, &vsockcfg, sizeof(vsockcfg)); 30 } 31 32 static int vhost_vsock_set_guest_cid(VirtIODevice *vdev) 33 { 34 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 35 VHostVSock *vsock = VHOST_VSOCK(vdev); 36 const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops; 37 int ret; 38 39 if (!vhost_ops->vhost_vsock_set_guest_cid) { 40 return -ENOSYS; 41 } 42 43 ret = vhost_ops->vhost_vsock_set_guest_cid(&vvc->vhost_dev, 44 vsock->conf.guest_cid); 45 if (ret < 0) { 46 return -errno; 47 } 48 return 0; 49 } 50 51 static int vhost_vsock_set_running(VirtIODevice *vdev, int start) 52 { 53 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 54 const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops; 55 int ret; 56 57 if (!vhost_ops->vhost_vsock_set_running) { 58 return -ENOSYS; 59 } 60 61 ret = vhost_ops->vhost_vsock_set_running(&vvc->vhost_dev, start); 62 if (ret < 0) { 63 return -errno; 64 } 65 return 0; 66 } 67 68 69 static void vhost_vsock_set_status(VirtIODevice *vdev, uint8_t status) 70 { 71 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 72 bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK; 73 int ret; 74 75 if (!vdev->vm_running) { 76 should_start = false; 77 } 78 79 if (vvc->vhost_dev.started == should_start) { 80 return; 81 } 82 83 if (should_start) { 84 ret = vhost_vsock_common_start(vdev); 85 if (ret < 0) { 86 return; 87 } 88 89 ret = vhost_vsock_set_running(vdev, 1); 90 if (ret < 0) { 91 vhost_vsock_common_stop(vdev); 92 error_report("Error starting vhost vsock: %d", -ret); 93 return; 94 } 95 } else { 96 ret = vhost_vsock_set_running(vdev, 0); 97 if (ret < 0) { 98 error_report("vhost vsock set running failed: %d", ret); 99 return; 100 } 101 102 vhost_vsock_common_stop(vdev); 103 } 104 } 105 106 static uint64_t vhost_vsock_get_features(VirtIODevice *vdev, 107 uint64_t requested_features, 108 Error **errp) 109 { 110 /* No feature bits used yet */ 111 return requested_features; 112 } 113 114 static const VMStateDescription vmstate_virtio_vhost_vsock = { 115 .name = "virtio-vhost_vsock", 116 .minimum_version_id = VHOST_VSOCK_SAVEVM_VERSION, 117 .version_id = VHOST_VSOCK_SAVEVM_VERSION, 118 .fields = (VMStateField[]) { 119 VMSTATE_VIRTIO_DEVICE, 120 VMSTATE_END_OF_LIST() 121 }, 122 .pre_save = vhost_vsock_common_pre_save, 123 .post_load = vhost_vsock_common_post_load, 124 }; 125 126 static void vhost_vsock_device_realize(DeviceState *dev, Error **errp) 127 { 128 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 129 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 130 VHostVSock *vsock = VHOST_VSOCK(dev); 131 int vhostfd; 132 int ret; 133 134 /* Refuse to use reserved CID numbers */ 135 if (vsock->conf.guest_cid <= 2) { 136 error_setg(errp, "guest-cid property must be greater than 2"); 137 return; 138 } 139 140 if (vsock->conf.guest_cid > UINT32_MAX) { 141 error_setg(errp, "guest-cid property must be a 32-bit number"); 142 return; 143 } 144 145 if (vsock->conf.vhostfd) { 146 vhostfd = monitor_fd_param(monitor_cur(), vsock->conf.vhostfd, errp); 147 if (vhostfd == -1) { 148 error_prepend(errp, "vhost-vsock: unable to parse vhostfd: "); 149 return; 150 } 151 } else { 152 vhostfd = open("/dev/vhost-vsock", O_RDWR); 153 if (vhostfd < 0) { 154 error_setg_errno(errp, errno, 155 "vhost-vsock: failed to open vhost device"); 156 return; 157 } 158 } 159 160 vhost_vsock_common_realize(vdev, "vhost-vsock"); 161 162 ret = vhost_dev_init(&vvc->vhost_dev, (void *)(uintptr_t)vhostfd, 163 VHOST_BACKEND_TYPE_KERNEL, 0); 164 if (ret < 0) { 165 error_setg_errno(errp, -ret, "vhost-vsock: vhost_dev_init failed"); 166 goto err_virtio; 167 } 168 169 ret = vhost_vsock_set_guest_cid(vdev); 170 if (ret < 0) { 171 error_setg_errno(errp, -ret, "vhost-vsock: unable to set guest cid"); 172 goto err_vhost_dev; 173 } 174 175 return; 176 177 err_vhost_dev: 178 vhost_dev_cleanup(&vvc->vhost_dev); 179 /* vhost_dev_cleanup() closes the vhostfd passed to vhost_dev_init() */ 180 vhostfd = -1; 181 err_virtio: 182 vhost_vsock_common_unrealize(vdev); 183 if (vhostfd >= 0) { 184 close(vhostfd); 185 } 186 return; 187 } 188 189 static void vhost_vsock_device_unrealize(DeviceState *dev) 190 { 191 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 192 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 193 194 /* This will stop vhost backend if appropriate. */ 195 vhost_vsock_set_status(vdev, 0); 196 197 vhost_dev_cleanup(&vvc->vhost_dev); 198 vhost_vsock_common_unrealize(vdev); 199 } 200 201 static Property vhost_vsock_properties[] = { 202 DEFINE_PROP_UINT64("guest-cid", VHostVSock, conf.guest_cid, 0), 203 DEFINE_PROP_STRING("vhostfd", VHostVSock, conf.vhostfd), 204 DEFINE_PROP_END_OF_LIST(), 205 }; 206 207 static void vhost_vsock_class_init(ObjectClass *klass, void *data) 208 { 209 DeviceClass *dc = DEVICE_CLASS(klass); 210 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 211 212 device_class_set_props(dc, vhost_vsock_properties); 213 dc->vmsd = &vmstate_virtio_vhost_vsock; 214 vdc->realize = vhost_vsock_device_realize; 215 vdc->unrealize = vhost_vsock_device_unrealize; 216 vdc->get_features = vhost_vsock_get_features; 217 vdc->get_config = vhost_vsock_get_config; 218 vdc->set_status = vhost_vsock_set_status; 219 } 220 221 static const TypeInfo vhost_vsock_info = { 222 .name = TYPE_VHOST_VSOCK, 223 .parent = TYPE_VHOST_VSOCK_COMMON, 224 .instance_size = sizeof(VHostVSock), 225 .class_init = vhost_vsock_class_init, 226 }; 227 228 static void vhost_vsock_register_types(void) 229 { 230 type_register_static(&vhost_vsock_info); 231 } 232 233 type_init(vhost_vsock_register_types) 234