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