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 = virtio_device_should_start(vdev, status); 74 int ret; 75 76 if (vhost_dev_is_started(&vvc->vhost_dev) == should_start) { 77 return; 78 } 79 80 if (should_start) { 81 ret = vhost_vsock_common_start(vdev); 82 if (ret < 0) { 83 return; 84 } 85 86 ret = vhost_vsock_set_running(vdev, 1); 87 if (ret < 0) { 88 vhost_vsock_common_stop(vdev); 89 error_report("Error starting vhost vsock: %d", -ret); 90 return; 91 } 92 } else { 93 ret = vhost_vsock_set_running(vdev, 0); 94 if (ret < 0) { 95 error_report("vhost vsock set running failed: %d", ret); 96 return; 97 } 98 99 vhost_vsock_common_stop(vdev); 100 } 101 } 102 103 static uint64_t vhost_vsock_get_features(VirtIODevice *vdev, 104 uint64_t requested_features, 105 Error **errp) 106 { 107 return vhost_vsock_common_get_features(vdev, requested_features, errp); 108 } 109 110 static const VMStateDescription vmstate_virtio_vhost_vsock = { 111 .name = "virtio-vhost_vsock", 112 .minimum_version_id = VHOST_VSOCK_SAVEVM_VERSION, 113 .version_id = VHOST_VSOCK_SAVEVM_VERSION, 114 .fields = (const VMStateField[]) { 115 VMSTATE_VIRTIO_DEVICE, 116 VMSTATE_END_OF_LIST() 117 }, 118 .pre_save = vhost_vsock_common_pre_save, 119 .post_load = vhost_vsock_common_post_load, 120 }; 121 122 static void vhost_vsock_device_realize(DeviceState *dev, Error **errp) 123 { 124 ERRP_GUARD(); 125 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 126 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 127 VHostVSock *vsock = VHOST_VSOCK(dev); 128 int vhostfd; 129 int ret; 130 131 /* Refuse to use reserved CID numbers */ 132 if (vsock->conf.guest_cid <= 2) { 133 error_setg(errp, "guest-cid property must be greater than 2"); 134 return; 135 } 136 137 if (vsock->conf.guest_cid > UINT32_MAX) { 138 error_setg(errp, "guest-cid property must be a 32-bit number"); 139 return; 140 } 141 142 if (vsock->conf.vhostfd) { 143 vhostfd = monitor_fd_param(monitor_cur(), vsock->conf.vhostfd, errp); 144 if (vhostfd == -1) { 145 error_prepend(errp, "vhost-vsock: unable to parse vhostfd: "); 146 return; 147 } 148 149 if (!g_unix_set_fd_nonblocking(vhostfd, true, NULL)) { 150 error_setg_errno(errp, errno, 151 "vhost-vsock: unable to set non-blocking mode"); 152 return; 153 } 154 } else { 155 vhostfd = open("/dev/vhost-vsock", O_RDWR); 156 if (vhostfd < 0) { 157 error_setg_errno(errp, errno, 158 "vhost-vsock: failed to open vhost device"); 159 return; 160 } 161 162 if (!g_unix_set_fd_nonblocking(vhostfd, true, NULL)) { 163 error_setg_errno(errp, errno, 164 "Failed to set FD nonblocking"); 165 return; 166 } 167 } 168 169 vhost_vsock_common_realize(vdev); 170 171 ret = vhost_dev_init(&vvc->vhost_dev, (void *)(uintptr_t)vhostfd, 172 VHOST_BACKEND_TYPE_KERNEL, 0, errp); 173 if (ret < 0) { 174 /* 175 * vhostfd is closed by vhost_dev_cleanup, which is called 176 * by vhost_dev_init on initialization error. 177 */ 178 goto err_virtio; 179 } 180 181 ret = vhost_vsock_set_guest_cid(vdev); 182 if (ret < 0) { 183 error_setg_errno(errp, -ret, "vhost-vsock: unable to set guest cid"); 184 goto err_vhost_dev; 185 } 186 187 return; 188 189 err_vhost_dev: 190 /* vhost_dev_cleanup() closes the vhostfd passed to vhost_dev_init() */ 191 vhost_dev_cleanup(&vvc->vhost_dev); 192 err_virtio: 193 vhost_vsock_common_unrealize(vdev); 194 } 195 196 static void vhost_vsock_device_unrealize(DeviceState *dev) 197 { 198 VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev); 199 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 200 201 /* This will stop vhost backend if appropriate. */ 202 vhost_vsock_set_status(vdev, 0); 203 204 vhost_dev_cleanup(&vvc->vhost_dev); 205 vhost_vsock_common_unrealize(vdev); 206 } 207 208 static Property vhost_vsock_properties[] = { 209 DEFINE_PROP_UINT64("guest-cid", VHostVSock, conf.guest_cid, 0), 210 DEFINE_PROP_STRING("vhostfd", VHostVSock, conf.vhostfd), 211 DEFINE_PROP_END_OF_LIST(), 212 }; 213 214 static void vhost_vsock_class_init(ObjectClass *klass, void *data) 215 { 216 DeviceClass *dc = DEVICE_CLASS(klass); 217 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 218 219 device_class_set_props(dc, vhost_vsock_properties); 220 dc->vmsd = &vmstate_virtio_vhost_vsock; 221 vdc->realize = vhost_vsock_device_realize; 222 vdc->unrealize = vhost_vsock_device_unrealize; 223 vdc->get_features = vhost_vsock_get_features; 224 vdc->get_config = vhost_vsock_get_config; 225 vdc->set_status = vhost_vsock_set_status; 226 } 227 228 static const TypeInfo vhost_vsock_info = { 229 .name = TYPE_VHOST_VSOCK, 230 .parent = TYPE_VHOST_VSOCK_COMMON, 231 .instance_size = sizeof(VHostVSock), 232 .class_init = vhost_vsock_class_init, 233 }; 234 235 static void vhost_vsock_register_types(void) 236 { 237 type_register_static(&vhost_vsock_info); 238 } 239 240 type_init(vhost_vsock_register_types) 241