1 /* 2 * vhost-user-scsi host device 3 * 4 * Copyright (c) 2016 Nutanix Inc. All rights reserved. 5 * 6 * Author: 7 * Felipe Franciosi <felipe@nutanix.com> 8 * 9 * This work is largely based on the "vhost-scsi" implementation by: 10 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> 11 * Nicholas Bellinger <nab@risingtidesystems.com> 12 * 13 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 14 * See the COPYING.LIB file in the top-level directory. 15 * 16 */ 17 18 #include "qemu/osdep.h" 19 #include "qapi/error.h" 20 #include "qemu/error-report.h" 21 #include "hw/fw-path-provider.h" 22 #include "hw/qdev-core.h" 23 #include "hw/qdev-properties.h" 24 #include "hw/qdev-properties-system.h" 25 #include "hw/virtio/vhost.h" 26 #include "hw/virtio/vhost-backend.h" 27 #include "hw/virtio/vhost-user-scsi.h" 28 #include "hw/virtio/virtio.h" 29 #include "chardev/char-fe.h" 30 #include "sysemu/sysemu.h" 31 32 /* Features supported by the host application */ 33 static const int user_feature_bits[] = { 34 VIRTIO_F_NOTIFY_ON_EMPTY, 35 VIRTIO_RING_F_INDIRECT_DESC, 36 VIRTIO_RING_F_EVENT_IDX, 37 VIRTIO_SCSI_F_HOTPLUG, 38 VIRTIO_F_RING_RESET, 39 VIRTIO_F_NOTIFICATION_DATA, 40 VHOST_INVALID_FEATURE_BIT 41 }; 42 43 static int vhost_user_scsi_start(VHostUserSCSI *s, Error **errp) 44 { 45 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 46 int ret; 47 48 ret = vhost_scsi_common_start(vsc, errp); 49 s->started_vu = !(ret < 0); 50 51 return ret; 52 } 53 54 static void vhost_user_scsi_stop(VHostUserSCSI *s) 55 { 56 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 57 58 if (!s->started_vu) { 59 return; 60 } 61 s->started_vu = false; 62 63 vhost_scsi_common_stop(vsc); 64 } 65 66 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) 67 { 68 VHostUserSCSI *s = (VHostUserSCSI *)vdev; 69 DeviceState *dev = DEVICE(vdev); 70 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 71 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 72 bool should_start = virtio_device_should_start(vdev, status); 73 Error *local_err = NULL; 74 int ret; 75 76 if (!s->connected) { 77 return; 78 } 79 80 if (vhost_dev_is_started(&vsc->dev) == should_start) { 81 return; 82 } 83 84 if (should_start) { 85 ret = vhost_user_scsi_start(s, &local_err); 86 if (ret < 0) { 87 error_reportf_err(local_err, 88 "unable to start vhost-user-scsi: %s: ", 89 strerror(-ret)); 90 qemu_chr_fe_disconnect(&vs->conf.chardev); 91 } 92 } else { 93 vhost_user_scsi_stop(s); 94 } 95 } 96 97 static void vhost_user_scsi_handle_output(VirtIODevice *vdev, VirtQueue *vq) 98 { 99 VHostUserSCSI *s = (VHostUserSCSI *)vdev; 100 DeviceState *dev = DEVICE(vdev); 101 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 102 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 103 104 Error *local_err = NULL; 105 int i, ret; 106 107 if (!vdev->start_on_kick) { 108 return; 109 } 110 111 if (!s->connected) { 112 return; 113 } 114 115 if (vhost_dev_is_started(&vsc->dev)) { 116 return; 117 } 118 119 /* 120 * Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start 121 * vhost here instead of waiting for .set_status(). 122 */ 123 ret = vhost_user_scsi_start(s, &local_err); 124 if (ret < 0) { 125 error_reportf_err(local_err, "vhost-user-scsi: vhost start failed: "); 126 qemu_chr_fe_disconnect(&vs->conf.chardev); 127 return; 128 } 129 130 /* Kick right away to begin processing requests already in vring */ 131 for (i = 0; i < vsc->dev.nvqs; i++) { 132 VirtQueue *kick_vq = virtio_get_queue(vdev, i); 133 134 if (!virtio_queue_get_desc_addr(vdev, i)) { 135 continue; 136 } 137 event_notifier_set(virtio_queue_get_host_notifier(kick_vq)); 138 } 139 } 140 141 static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) 142 { 143 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 144 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 145 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 146 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 147 int ret = 0; 148 149 if (s->connected) { 150 return 0; 151 } 152 153 vsc->dev.num_queues = vs->conf.num_queues; 154 vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 155 vsc->dev.vqs = s->vhost_vqs; 156 vsc->dev.vq_index = 0; 157 vsc->dev.backend_features = 0; 158 159 ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, 160 errp); 161 if (ret < 0) { 162 return ret; 163 } 164 165 s->connected = true; 166 167 /* restore vhost state */ 168 if (virtio_device_started(vdev, vdev->status)) { 169 ret = vhost_user_scsi_start(s, errp); 170 } 171 172 return ret; 173 } 174 175 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); 176 177 static void vhost_user_scsi_disconnect(DeviceState *dev) 178 { 179 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 180 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 181 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 182 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 183 184 if (!s->connected) { 185 goto done; 186 } 187 s->connected = false; 188 189 vhost_user_scsi_stop(s); 190 191 vhost_dev_cleanup(&vsc->dev); 192 193 done: 194 /* Re-instate the event handler for new connections */ 195 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 196 vhost_user_scsi_event, NULL, dev, NULL, true); 197 } 198 199 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) 200 { 201 DeviceState *dev = opaque; 202 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 203 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 204 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 205 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 206 Error *local_err = NULL; 207 208 switch (event) { 209 case CHR_EVENT_OPENED: 210 if (vhost_user_scsi_connect(dev, &local_err) < 0) { 211 error_report_err(local_err); 212 qemu_chr_fe_disconnect(&vs->conf.chardev); 213 return; 214 } 215 break; 216 case CHR_EVENT_CLOSED: 217 /* defer close until later to avoid circular close */ 218 vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, 219 vhost_user_scsi_disconnect); 220 break; 221 case CHR_EVENT_BREAK: 222 case CHR_EVENT_MUX_IN: 223 case CHR_EVENT_MUX_OUT: 224 /* Ignore */ 225 break; 226 } 227 } 228 229 static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) 230 { 231 DeviceState *dev = DEVICE(s); 232 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 233 int ret; 234 235 s->connected = false; 236 237 ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); 238 if (ret < 0) { 239 return ret; 240 } 241 242 ret = vhost_user_scsi_connect(dev, errp); 243 if (ret < 0) { 244 qemu_chr_fe_disconnect(&vs->conf.chardev); 245 return ret; 246 } 247 assert(s->connected); 248 249 return 0; 250 } 251 252 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) 253 { 254 ERRP_GUARD(); 255 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 256 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 257 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 258 Error *err = NULL; 259 int ret; 260 int retries = VU_REALIZE_CONN_RETRIES; 261 262 if (!vs->conf.chardev.chr) { 263 error_setg(errp, "vhost-user-scsi: missing chardev"); 264 return; 265 } 266 267 virtio_scsi_common_realize(dev, vhost_user_scsi_handle_output, 268 vhost_user_scsi_handle_output, 269 vhost_user_scsi_handle_output, &err); 270 if (err != NULL) { 271 error_propagate(errp, err); 272 return; 273 } 274 275 if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) { 276 goto free_virtio; 277 } 278 279 vsc->inflight = g_new0(struct vhost_inflight, 1); 280 s->vhost_vqs = g_new0(struct vhost_virtqueue, 281 VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); 282 283 assert(!*errp); 284 do { 285 if (*errp) { 286 error_prepend(errp, "Reconnecting after error: "); 287 error_report_err(*errp); 288 *errp = NULL; 289 } 290 ret = vhost_user_scsi_realize_connect(s, errp); 291 } while (ret < 0 && retries--); 292 293 if (ret < 0) { 294 goto free_vhost; 295 } 296 297 /* we're fully initialized, now we can operate, so add the handler */ 298 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 299 vhost_user_scsi_event, NULL, (void *)dev, 300 NULL, true); 301 /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ 302 vsc->channel = 0; 303 vsc->lun = 0; 304 vsc->target = vs->conf.boot_tpgt; 305 306 return; 307 308 free_vhost: 309 g_free(s->vhost_vqs); 310 s->vhost_vqs = NULL; 311 g_free(vsc->inflight); 312 vsc->inflight = NULL; 313 vhost_user_cleanup(&s->vhost_user); 314 315 free_virtio: 316 virtio_scsi_common_unrealize(dev); 317 } 318 319 static void vhost_user_scsi_unrealize(DeviceState *dev) 320 { 321 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 322 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 323 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 324 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 325 326 /* This will stop the vhost backend. */ 327 vhost_user_scsi_set_status(vdev, 0); 328 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, 329 NULL, false); 330 331 vhost_dev_cleanup(&vsc->dev); 332 g_free(s->vhost_vqs); 333 s->vhost_vqs = NULL; 334 335 vhost_dev_free_inflight(vsc->inflight); 336 g_free(vsc->inflight); 337 vsc->inflight = NULL; 338 339 vhost_user_cleanup(&s->vhost_user); 340 virtio_scsi_common_unrealize(dev); 341 } 342 343 static Property vhost_user_scsi_properties[] = { 344 DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev), 345 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 346 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 347 VIRTIO_SCSI_AUTO_NUM_QUEUES), 348 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 349 128), 350 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 351 0xFFFF), 352 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 353 DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features, 354 VIRTIO_SCSI_F_HOTPLUG, 355 true), 356 DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features, 357 VIRTIO_SCSI_F_CHANGE, 358 true), 359 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 360 VIRTIO_SCSI_F_T10_PI, 361 false), 362 DEFINE_PROP_END_OF_LIST(), 363 }; 364 365 static void vhost_user_scsi_reset(VirtIODevice *vdev) 366 { 367 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 368 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 369 370 vhost_dev_free_inflight(vsc->inflight); 371 } 372 373 static struct vhost_dev *vhost_user_scsi_get_vhost(VirtIODevice *vdev) 374 { 375 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev); 376 return &vsc->dev; 377 } 378 379 static const VMStateDescription vmstate_vhost_scsi = { 380 .name = "virtio-scsi", 381 .minimum_version_id = 1, 382 .version_id = 1, 383 .fields = (const VMStateField[]) { 384 VMSTATE_VIRTIO_DEVICE, 385 VMSTATE_END_OF_LIST() 386 }, 387 }; 388 389 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data) 390 { 391 DeviceClass *dc = DEVICE_CLASS(klass); 392 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 393 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 394 395 device_class_set_props(dc, vhost_user_scsi_properties); 396 dc->vmsd = &vmstate_vhost_scsi; 397 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 398 vdc->realize = vhost_user_scsi_realize; 399 vdc->unrealize = vhost_user_scsi_unrealize; 400 vdc->get_features = vhost_scsi_common_get_features; 401 vdc->set_config = vhost_scsi_common_set_config; 402 vdc->set_status = vhost_user_scsi_set_status; 403 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 404 vdc->reset = vhost_user_scsi_reset; 405 vdc->get_vhost = vhost_user_scsi_get_vhost; 406 } 407 408 static void vhost_user_scsi_instance_init(Object *obj) 409 { 410 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 411 412 vsc->feature_bits = user_feature_bits; 413 414 /* Add the bootindex property for this object */ 415 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 416 DEVICE(vsc)); 417 } 418 419 static const TypeInfo vhost_user_scsi_info = { 420 .name = TYPE_VHOST_USER_SCSI, 421 .parent = TYPE_VHOST_SCSI_COMMON, 422 .instance_size = sizeof(VHostUserSCSI), 423 .class_init = vhost_user_scsi_class_init, 424 .instance_init = vhost_user_scsi_instance_init, 425 .interfaces = (InterfaceInfo[]) { 426 { TYPE_FW_PATH_PROVIDER }, 427 { } 428 }, 429 }; 430 431 static void virtio_register_types(void) 432 { 433 type_register_static(&vhost_user_scsi_info); 434 } 435 436 type_init(virtio_register_types) 437