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 "qemu/sockets.h" 20 #include "hw/qdev-properties.h" 21 #include "hw/virtio/vhost-vsock.h" 22 #include "monitor/monitor.h" 23 24 static void vhost_vsock_get_config(VirtIODevice *vdev, uint8_t *config) 25 { 26 VHostVSock *vsock = VHOST_VSOCK(vdev); 27 struct virtio_vsock_config vsockcfg = {}; 28 29 virtio_stq_p(vdev, &vsockcfg.guest_cid, vsock->conf.guest_cid); 30 memcpy(config, &vsockcfg, sizeof(vsockcfg)); 31 } 32 33 static int vhost_vsock_set_guest_cid(VirtIODevice *vdev) 34 { 35 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 36 VHostVSock *vsock = VHOST_VSOCK(vdev); 37 const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops; 38 int ret; 39 40 if (!vhost_ops->vhost_vsock_set_guest_cid) { 41 return -ENOSYS; 42 } 43 44 ret = vhost_ops->vhost_vsock_set_guest_cid(&vvc->vhost_dev, 45 vsock->conf.guest_cid); 46 if (ret < 0) { 47 return -errno; 48 } 49 return 0; 50 } 51 52 static int vhost_vsock_set_running(VirtIODevice *vdev, int start) 53 { 54 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 55 const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops; 56 int ret; 57 58 if (!vhost_ops->vhost_vsock_set_running) { 59 return -ENOSYS; 60 } 61 62 ret = vhost_ops->vhost_vsock_set_running(&vvc->vhost_dev, start); 63 if (ret < 0) { 64 return -errno; 65 } 66 return 0; 67 } 68 69 70 static void vhost_vsock_set_status(VirtIODevice *vdev, uint8_t status) 71 { 72 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); 73 bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK; 74 int ret; 75 76 if (!vdev->vm_running) { 77 should_start = false; 78 } 79 80 if (vvc->vhost_dev.started == should_start) { 81 return; 82 } 83 84 if (should_start) { 85 ret = vhost_vsock_common_start(vdev); 86 if (ret < 0) { 87 return; 88 } 89 90 ret = vhost_vsock_set_running(vdev, 1); 91 if (ret < 0) { 92 vhost_vsock_common_stop(vdev); 93 error_report("Error starting vhost vsock: %d", -ret); 94 return; 95 } 96 } else { 97 ret = vhost_vsock_set_running(vdev, 0); 98 if (ret < 0) { 99 error_report("vhost vsock set running failed: %d", ret); 100 return; 101 } 102 103 vhost_vsock_common_stop(vdev); 104 } 105 } 106 107 static uint64_t vhost_vsock_get_features(VirtIODevice *vdev, 108 uint64_t requested_features, 109 Error **errp) 110 { 111 /* No feature bits used yet */ 112 return requested_features; 113 } 114 115 static const VMStateDescription vmstate_virtio_vhost_vsock = { 116 .name = "virtio-vhost_vsock", 117 .minimum_version_id = VHOST_VSOCK_SAVEVM_VERSION, 118 .version_id = VHOST_VSOCK_SAVEVM_VERSION, 119 .fields = (VMStateField[]) { 120 VMSTATE_VIRTIO_DEVICE, 121 VMSTATE_END_OF_LIST() 122 }, 123 .pre_save = vhost_vsock_common_pre_save, 124 .post_load = vhost_vsock_common_post_load, 125 }; 126 127 static void vhost_vsock_device_realize(DeviceState *dev, Error **errp) 128 { 129 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 130 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 131 VHostVSock *vsock = VHOST_VSOCK(dev); 132 int vhostfd; 133 int ret; 134 135 /* Refuse to use reserved CID numbers */ 136 if (vsock->conf.guest_cid <= 2) { 137 error_setg(errp, "guest-cid property must be greater than 2"); 138 return; 139 } 140 141 if (vsock->conf.guest_cid > UINT32_MAX) { 142 error_setg(errp, "guest-cid property must be a 32-bit number"); 143 return; 144 } 145 146 if (vsock->conf.vhostfd) { 147 vhostfd = monitor_fd_param(monitor_cur(), vsock->conf.vhostfd, errp); 148 if (vhostfd == -1) { 149 error_prepend(errp, "vhost-vsock: unable to parse vhostfd: "); 150 return; 151 } 152 153 ret = qemu_try_set_nonblock(vhostfd); 154 if (ret < 0) { 155 error_setg_errno(errp, -ret, 156 "vhost-vsock: unable to set non-blocking mode"); 157 return; 158 } 159 } else { 160 vhostfd = open("/dev/vhost-vsock", O_RDWR); 161 if (vhostfd < 0) { 162 error_setg_errno(errp, errno, 163 "vhost-vsock: failed to open vhost device"); 164 return; 165 } 166 167 qemu_set_nonblock(vhostfd); 168 } 169 170 vhost_vsock_common_realize(vdev, "vhost-vsock"); 171 172 ret = vhost_dev_init(&vvc->vhost_dev, (void *)(uintptr_t)vhostfd, 173 VHOST_BACKEND_TYPE_KERNEL, 0); 174 if (ret < 0) { 175 error_setg_errno(errp, -ret, "vhost-vsock: vhost_dev_init failed"); 176 goto err_virtio; 177 } 178 179 ret = vhost_vsock_set_guest_cid(vdev); 180 if (ret < 0) { 181 error_setg_errno(errp, -ret, "vhost-vsock: unable to set guest cid"); 182 goto err_vhost_dev; 183 } 184 185 return; 186 187 err_vhost_dev: 188 vhost_dev_cleanup(&vvc->vhost_dev); 189 /* vhost_dev_cleanup() closes the vhostfd passed to vhost_dev_init() */ 190 vhostfd = -1; 191 err_virtio: 192 vhost_vsock_common_unrealize(vdev); 193 if (vhostfd >= 0) { 194 close(vhostfd); 195 } 196 return; 197 } 198 199 static void vhost_vsock_device_unrealize(DeviceState *dev) 200 { 201 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 202 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 203 204 /* This will stop vhost backend if appropriate. */ 205 vhost_vsock_set_status(vdev, 0); 206 207 vhost_dev_cleanup(&vvc->vhost_dev); 208 vhost_vsock_common_unrealize(vdev); 209 } 210 211 static Property vhost_vsock_properties[] = { 212 DEFINE_PROP_UINT64("guest-cid", VHostVSock, conf.guest_cid, 0), 213 DEFINE_PROP_STRING("vhostfd", VHostVSock, conf.vhostfd), 214 DEFINE_PROP_END_OF_LIST(), 215 }; 216 217 static void vhost_vsock_class_init(ObjectClass *klass, void *data) 218 { 219 DeviceClass *dc = DEVICE_CLASS(klass); 220 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 221 222 device_class_set_props(dc, vhost_vsock_properties); 223 dc->vmsd = &vmstate_virtio_vhost_vsock; 224 vdc->realize = vhost_vsock_device_realize; 225 vdc->unrealize = vhost_vsock_device_unrealize; 226 vdc->get_features = vhost_vsock_get_features; 227 vdc->get_config = vhost_vsock_get_config; 228 vdc->set_status = vhost_vsock_set_status; 229 } 230 231 static const TypeInfo vhost_vsock_info = { 232 .name = TYPE_VHOST_VSOCK, 233 .parent = TYPE_VHOST_VSOCK_COMMON, 234 .instance_size = sizeof(VHostVSock), 235 .class_init = vhost_vsock_class_init, 236 }; 237 238 static void vhost_vsock_register_types(void) 239 { 240 type_register_static(&vhost_vsock_info); 241 } 242 243 type_init(vhost_vsock_register_types) 244