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 s->connected = true; 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 /* restore vhost state */ 165 if (virtio_device_started(vdev, vdev->status)) { 166 ret = vhost_user_scsi_start(s, errp); 167 } 168 169 return ret; 170 } 171 172 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); 173 174 static void vhost_user_scsi_disconnect(DeviceState *dev) 175 { 176 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 177 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 178 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 179 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 180 181 if (!s->connected) { 182 return; 183 } 184 s->connected = false; 185 186 vhost_user_scsi_stop(s); 187 188 vhost_dev_cleanup(&vsc->dev); 189 190 /* Re-instate the event handler for new connections */ 191 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 192 vhost_user_scsi_event, NULL, dev, NULL, true); 193 } 194 195 static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) 196 { 197 DeviceState *dev = opaque; 198 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 199 VHostUserSCSI *s = VHOST_USER_SCSI(vdev); 200 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 201 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 202 Error *local_err = NULL; 203 204 switch (event) { 205 case CHR_EVENT_OPENED: 206 if (vhost_user_scsi_connect(dev, &local_err) < 0) { 207 error_report_err(local_err); 208 qemu_chr_fe_disconnect(&vs->conf.chardev); 209 return; 210 } 211 break; 212 case CHR_EVENT_CLOSED: 213 /* defer close until later to avoid circular close */ 214 vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, 215 vhost_user_scsi_disconnect, 216 vhost_user_scsi_event); 217 break; 218 case CHR_EVENT_BREAK: 219 case CHR_EVENT_MUX_IN: 220 case CHR_EVENT_MUX_OUT: 221 /* Ignore */ 222 break; 223 } 224 } 225 226 static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) 227 { 228 DeviceState *dev = DEVICE(s); 229 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 230 int ret; 231 232 s->connected = false; 233 234 ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); 235 if (ret < 0) { 236 return ret; 237 } 238 239 ret = vhost_user_scsi_connect(dev, errp); 240 if (ret < 0) { 241 qemu_chr_fe_disconnect(&vs->conf.chardev); 242 return ret; 243 } 244 assert(s->connected); 245 246 return 0; 247 } 248 249 static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) 250 { 251 ERRP_GUARD(); 252 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 253 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 254 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 255 Error *err = NULL; 256 int ret; 257 int retries = VU_REALIZE_CONN_RETRIES; 258 259 if (!vs->conf.chardev.chr) { 260 error_setg(errp, "vhost-user-scsi: missing chardev"); 261 return; 262 } 263 264 virtio_scsi_common_realize(dev, vhost_user_scsi_handle_output, 265 vhost_user_scsi_handle_output, 266 vhost_user_scsi_handle_output, &err); 267 if (err != NULL) { 268 error_propagate(errp, err); 269 return; 270 } 271 272 if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) { 273 goto free_virtio; 274 } 275 276 vsc->inflight = g_new0(struct vhost_inflight, 1); 277 s->vhost_vqs = g_new0(struct vhost_virtqueue, 278 VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); 279 280 assert(!*errp); 281 do { 282 if (*errp) { 283 error_prepend(errp, "Reconnecting after error: "); 284 error_report_err(*errp); 285 *errp = NULL; 286 } 287 ret = vhost_user_scsi_realize_connect(s, errp); 288 } while (ret < 0 && retries--); 289 290 if (ret < 0) { 291 goto free_vhost; 292 } 293 294 /* we're fully initialized, now we can operate, so add the handler */ 295 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, 296 vhost_user_scsi_event, NULL, (void *)dev, 297 NULL, true); 298 /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ 299 vsc->channel = 0; 300 vsc->lun = 0; 301 vsc->target = vs->conf.boot_tpgt; 302 303 return; 304 305 free_vhost: 306 g_free(s->vhost_vqs); 307 s->vhost_vqs = NULL; 308 g_free(vsc->inflight); 309 vsc->inflight = NULL; 310 vhost_user_cleanup(&s->vhost_user); 311 312 free_virtio: 313 virtio_scsi_common_unrealize(dev); 314 } 315 316 static void vhost_user_scsi_unrealize(DeviceState *dev) 317 { 318 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 319 VHostUserSCSI *s = VHOST_USER_SCSI(dev); 320 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 321 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 322 323 /* This will stop the vhost backend. */ 324 vhost_user_scsi_set_status(vdev, 0); 325 qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, 326 NULL, false); 327 328 vhost_dev_cleanup(&vsc->dev); 329 g_free(s->vhost_vqs); 330 s->vhost_vqs = NULL; 331 332 vhost_dev_free_inflight(vsc->inflight); 333 g_free(vsc->inflight); 334 vsc->inflight = NULL; 335 336 vhost_user_cleanup(&s->vhost_user); 337 virtio_scsi_common_unrealize(dev); 338 } 339 340 static Property vhost_user_scsi_properties[] = { 341 DEFINE_PROP_CHR("chardev", VirtIOSCSICommon, conf.chardev), 342 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 343 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 344 VIRTIO_SCSI_AUTO_NUM_QUEUES), 345 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 346 128), 347 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 348 0xFFFF), 349 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 350 DEFINE_PROP_BIT64("hotplug", VHostSCSICommon, host_features, 351 VIRTIO_SCSI_F_HOTPLUG, 352 true), 353 DEFINE_PROP_BIT64("param_change", VHostSCSICommon, host_features, 354 VIRTIO_SCSI_F_CHANGE, 355 true), 356 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 357 VIRTIO_SCSI_F_T10_PI, 358 false), 359 DEFINE_PROP_END_OF_LIST(), 360 }; 361 362 static const VMStateDescription vmstate_vhost_scsi = { 363 .name = "virtio-scsi", 364 .minimum_version_id = 1, 365 .version_id = 1, 366 .fields = (VMStateField[]) { 367 VMSTATE_VIRTIO_DEVICE, 368 VMSTATE_END_OF_LIST() 369 }, 370 }; 371 372 static void vhost_user_scsi_class_init(ObjectClass *klass, void *data) 373 { 374 DeviceClass *dc = DEVICE_CLASS(klass); 375 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 376 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 377 378 device_class_set_props(dc, vhost_user_scsi_properties); 379 dc->vmsd = &vmstate_vhost_scsi; 380 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 381 vdc->realize = vhost_user_scsi_realize; 382 vdc->unrealize = vhost_user_scsi_unrealize; 383 vdc->get_features = vhost_scsi_common_get_features; 384 vdc->set_config = vhost_scsi_common_set_config; 385 vdc->set_status = vhost_user_scsi_set_status; 386 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 387 } 388 389 static void vhost_user_scsi_instance_init(Object *obj) 390 { 391 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 392 393 vsc->feature_bits = user_feature_bits; 394 395 /* Add the bootindex property for this object */ 396 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 397 DEVICE(vsc)); 398 } 399 400 static const TypeInfo vhost_user_scsi_info = { 401 .name = TYPE_VHOST_USER_SCSI, 402 .parent = TYPE_VHOST_SCSI_COMMON, 403 .instance_size = sizeof(VHostUserSCSI), 404 .class_init = vhost_user_scsi_class_init, 405 .instance_init = vhost_user_scsi_instance_init, 406 .interfaces = (InterfaceInfo[]) { 407 { TYPE_FW_PATH_PROVIDER }, 408 { } 409 }, 410 }; 411 412 static void virtio_register_types(void) 413 { 414 type_register_static(&vhost_user_scsi_info); 415 } 416 417 type_init(virtio_register_types) 418