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