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_IN_ORDER, 40 VIRTIO_F_NOTIFICATION_DATA, 41 VHOST_INVALID_FEATURE_BIT 42 }; 43 44 static int vhost_user_scsi_start(VHostUserSCSI *s, Error **errp) 45 { 46 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 47 int ret; 48 49 ret = vhost_scsi_common_start(vsc, errp); 50 s->started_vu = !(ret < 0); 51 52 return ret; 53 } 54 55 static void vhost_user_scsi_stop(VHostUserSCSI *s) 56 { 57 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 58 59 if (!s->started_vu) { 60 return; 61 } 62 s->started_vu = false; 63 64 vhost_scsi_common_stop(vsc); 65 } 66 67 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) 68 { 69 VHostUserSCSI *s = (VHostUserSCSI *)vdev; 70 DeviceState *dev = DEVICE(vdev); 71 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 72 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 73 bool should_start = virtio_device_should_start(vdev, status); 74 Error *local_err = NULL; 75 int ret; 76 77 if (!s->connected) { 78 return; 79 } 80 81 if (vhost_dev_is_started(&vsc->dev) == should_start) { 82 return; 83 } 84 85 if (should_start) { 86 ret = vhost_user_scsi_start(s, &local_err); 87 if (ret < 0) { 88 error_reportf_err(local_err, 89 "unable to start vhost-user-scsi: %s: ", 90 strerror(-ret)); 91 qemu_chr_fe_disconnect(&vs->conf.chardev); 92 } 93 } else { 94 vhost_user_scsi_stop(s); 95 } 96 } 97 98 static void vhost_user_scsi_handle_output(VirtIODevice *vdev, VirtQueue *vq) 99 { 100 VHostUserSCSI *s = (VHostUserSCSI *)vdev; 101 DeviceState *dev = DEVICE(vdev); 102 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 103 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 104 105 Error *local_err = NULL; 106 int i, ret; 107 108 if (!vdev->start_on_kick) { 109 return; 110 } 111 112 if (!s->connected) { 113 return; 114 } 115 116 if (vhost_dev_is_started(&vsc->dev)) { 117 return; 118 } 119 120 /* 121 * Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start 122 * vhost here instead of waiting for .set_status(). 123 */ 124 ret = vhost_user_scsi_start(s, &local_err); 125 if (ret < 0) { 126 error_reportf_err(local_err, "vhost-user-scsi: vhost start failed: "); 127 qemu_chr_fe_disconnect(&vs->conf.chardev); 128 return; 129 } 130 131 /* Kick right away to begin processing requests already in vring */ 132 for (i = 0; i < vsc->dev.nvqs; i++) { 133 VirtQueue *kick_vq = virtio_get_queue(vdev, i); 134 135 if (!virtio_queue_get_desc_addr(vdev, i)) { 136 continue; 137 } 138 event_notifier_set(virtio_queue_get_host_notifier(kick_vq)); 139 } 140 } 141 142 static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) 143 { 144 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 145 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 146 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 147 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 148 int ret = 0; 149 150 if (s->connected) { 151 return 0; 152 } 153 154 vsc->dev.num_queues = vs->conf.num_queues; 155 vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 156 vsc->dev.vqs = s->vhost_vqs; 157 vsc->dev.vq_index = 0; 158 vsc->dev.backend_features = 0; 159 160 ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, 161 errp); 162 if (ret < 0) { 163 return ret; 164 } 165 166 s->connected = true; 167 168 /* restore vhost state */ 169 if (virtio_device_started(vdev, vdev->status)) { 170 ret = vhost_user_scsi_start(s, errp); 171 } 172 173 return ret; 174 } 175 176 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); 177 178 static void vhost_user_scsi_disconnect(DeviceState *dev) 179 { 180 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 181 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 182 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 183 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 184 185 if (!s->connected) { 186 goto done; 187 } 188 s->connected = false; 189 190 vhost_user_scsi_stop(s); 191 192 vhost_dev_cleanup(&vsc->dev); 193 194 done: 195 /* Re-instate the event handler for new connections */ 196 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 197 vhost_user_scsi_event, NULL, dev, NULL, true); 198 } 199 200 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) 201 { 202 DeviceState *dev = opaque; 203 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 204 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 205 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 206 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 207 Error *local_err = NULL; 208 209 switch (event) { 210 case CHR_EVENT_OPENED: 211 if (vhost_user_scsi_connect(dev, &local_err) < 0) { 212 error_report_err(local_err); 213 qemu_chr_fe_disconnect(&vs->conf.chardev); 214 return; 215 } 216 break; 217 case CHR_EVENT_CLOSED: 218 /* defer close until later to avoid circular close */ 219 vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, 220 vhost_user_scsi_disconnect); 221 break; 222 case CHR_EVENT_BREAK: 223 case CHR_EVENT_MUX_IN: 224 case CHR_EVENT_MUX_OUT: 225 /* Ignore */ 226 break; 227 } 228 } 229 230 static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) 231 { 232 DeviceState *dev = DEVICE(s); 233 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 234 int ret; 235 236 s->connected = false; 237 238 ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); 239 if (ret < 0) { 240 return ret; 241 } 242 243 ret = vhost_user_scsi_connect(dev, errp); 244 if (ret < 0) { 245 qemu_chr_fe_disconnect(&vs->conf.chardev); 246 return ret; 247 } 248 assert(s->connected); 249 250 return 0; 251 } 252 253 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) 254 { 255 ERRP_GUARD(); 256 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 257 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 258 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 259 Error *err = NULL; 260 int ret; 261 int retries = VU_REALIZE_CONN_RETRIES; 262 263 if (!vs->conf.chardev.chr) { 264 error_setg(errp, "vhost-user-scsi: missing chardev"); 265 return; 266 } 267 268 virtio_scsi_common_realize(dev, vhost_user_scsi_handle_output, 269 vhost_user_scsi_handle_output, 270 vhost_user_scsi_handle_output, &err); 271 if (err != NULL) { 272 error_propagate(errp, err); 273 return; 274 } 275 276 if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) { 277 goto free_virtio; 278 } 279 280 vsc->inflight = g_new0(struct vhost_inflight, 1); 281 s->vhost_vqs = g_new0(struct vhost_virtqueue, 282 VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); 283 284 assert(!*errp); 285 do { 286 if (*errp) { 287 error_prepend(errp, "Reconnecting after error: "); 288 error_report_err(*errp); 289 *errp = NULL; 290 } 291 ret = vhost_user_scsi_realize_connect(s, errp); 292 } while (ret < 0 && retries--); 293 294 if (ret < 0) { 295 goto free_vhost; 296 } 297 298 /* we're fully initialized, now we can operate, so add the handler */ 299 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 300 vhost_user_scsi_event, NULL, (void *)dev, 301 NULL, true); 302 /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ 303 vsc->channel = 0; 304 vsc->lun = 0; 305 vsc->target = vs->conf.boot_tpgt; 306 307 return; 308 309 free_vhost: 310 g_free(s->vhost_vqs); 311 s->vhost_vqs = NULL; 312 g_free(vsc->inflight); 313 vsc->inflight = NULL; 314 vhost_user_cleanup(&s->vhost_user); 315 316 free_virtio: 317 virtio_scsi_common_unrealize(dev); 318 } 319 320 static void vhost_user_scsi_unrealize(DeviceState *dev) 321 { 322 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 323 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 324 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 325 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 326 327 /* This will stop the vhost backend. */ 328 vhost_user_scsi_set_status(vdev, 0); 329 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, 330 NULL, false); 331 332 vhost_dev_cleanup(&vsc->dev); 333 g_free(s->vhost_vqs); 334 s->vhost_vqs = NULL; 335 336 vhost_dev_free_inflight(vsc->inflight); 337 g_free(vsc->inflight); 338 vsc->inflight = NULL; 339 340 vhost_user_cleanup(&s->vhost_user); 341 virtio_scsi_common_unrealize(dev); 342 } 343 344 static Property vhost_user_scsi_properties[] = { 345 DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev), 346 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 347 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 348 VIRTIO_SCSI_AUTO_NUM_QUEUES), 349 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 350 128), 351 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 352 0xFFFF), 353 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 354 DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features, 355 VIRTIO_SCSI_F_HOTPLUG, 356 true), 357 DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features, 358 VIRTIO_SCSI_F_CHANGE, 359 true), 360 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 361 VIRTIO_SCSI_F_T10_PI, 362 false), 363 DEFINE_PROP_END_OF_LIST(), 364 }; 365 366 static void vhost_user_scsi_reset(VirtIODevice *vdev) 367 { 368 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 369 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 370 371 vhost_dev_free_inflight(vsc->inflight); 372 } 373 374 static struct vhost_dev *vhost_user_scsi_get_vhost(VirtIODevice *vdev) 375 { 376 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev); 377 return &vsc->dev; 378 } 379 380 static const VMStateDescription vmstate_vhost_scsi = { 381 .name = "virtio-scsi", 382 .minimum_version_id = 1, 383 .version_id = 1, 384 .fields = (const VMStateField[]) { 385 VMSTATE_VIRTIO_DEVICE, 386 VMSTATE_END_OF_LIST() 387 }, 388 }; 389 390 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data) 391 { 392 DeviceClass *dc = DEVICE_CLASS(klass); 393 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 394 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 395 396 device_class_set_props(dc, vhost_user_scsi_properties); 397 dc->vmsd = &vmstate_vhost_scsi; 398 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 399 vdc->realize = vhost_user_scsi_realize; 400 vdc->unrealize = vhost_user_scsi_unrealize; 401 vdc->get_features = vhost_scsi_common_get_features; 402 vdc->set_config = vhost_scsi_common_set_config; 403 vdc->set_status = vhost_user_scsi_set_status; 404 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 405 vdc->reset = vhost_user_scsi_reset; 406 vdc->get_vhost = vhost_user_scsi_get_vhost; 407 } 408 409 static void vhost_user_scsi_instance_init(Object *obj) 410 { 411 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 412 413 vsc->feature_bits = user_feature_bits; 414 415 /* Add the bootindex property for this object */ 416 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 417 DEVICE(vsc)); 418 } 419 420 static const TypeInfo vhost_user_scsi_info = { 421 .name = TYPE_VHOST_USER_SCSI, 422 .parent = TYPE_VHOST_SCSI_COMMON, 423 .instance_size = sizeof(VHostUserSCSI), 424 .class_init = vhost_user_scsi_class_init, 425 .instance_init = vhost_user_scsi_instance_init, 426 .interfaces = (InterfaceInfo[]) { 427 { TYPE_FW_PATH_PROVIDER }, 428 { } 429 }, 430 }; 431 432 static void virtio_register_types(void) 433 { 434 type_register_static(&vhost_user_scsi_info); 435 } 436 437 type_init(virtio_register_types) 438