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