1 /* 2 * vhost_scsi host device 3 * 4 * Copyright IBM, Corp. 2011 5 * 6 * Authors: 7 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> 8 * 9 * Changes for QEMU mainline + tcm_vhost kernel upstream: 10 * Nicholas Bellinger <nab@risingtidesystems.com> 11 * 12 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 13 * See the COPYING.LIB file in the top-level directory. 14 * 15 */ 16 17 #include <sys/ioctl.h> 18 #include "config.h" 19 #include "qemu/error-report.h" 20 #include "qemu/queue.h" 21 #include "monitor/monitor.h" 22 #include "migration/migration.h" 23 #include "hw/virtio/vhost-scsi.h" 24 #include "hw/virtio/vhost.h" 25 #include "hw/virtio/virtio-scsi.h" 26 #include "hw/virtio/virtio-bus.h" 27 #include "hw/virtio/virtio-access.h" 28 #include "hw/fw-path-provider.h" 29 30 /* Features supported by host kernel. */ 31 static const int kernel_feature_bits[] = { 32 VIRTIO_F_NOTIFY_ON_EMPTY, 33 VIRTIO_RING_F_INDIRECT_DESC, 34 VIRTIO_RING_F_EVENT_IDX, 35 VIRTIO_SCSI_F_HOTPLUG, 36 VHOST_INVALID_FEATURE_BIT 37 }; 38 39 static int vhost_scsi_set_endpoint(VHostSCSI *s) 40 { 41 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 42 const VhostOps *vhost_ops = s->dev.vhost_ops; 43 struct vhost_scsi_target backend; 44 int ret; 45 46 memset(&backend, 0, sizeof(backend)); 47 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 48 ret = vhost_ops->vhost_call(&s->dev, VHOST_SCSI_SET_ENDPOINT, &backend); 49 if (ret < 0) { 50 return -errno; 51 } 52 return 0; 53 } 54 55 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 56 { 57 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 58 struct vhost_scsi_target backend; 59 const VhostOps *vhost_ops = s->dev.vhost_ops; 60 61 memset(&backend, 0, sizeof(backend)); 62 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 63 vhost_ops->vhost_call(&s->dev, VHOST_SCSI_CLEAR_ENDPOINT, &backend); 64 } 65 66 static int vhost_scsi_start(VHostSCSI *s) 67 { 68 int ret, abi_version, i; 69 VirtIODevice *vdev = VIRTIO_DEVICE(s); 70 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 71 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 72 const VhostOps *vhost_ops = s->dev.vhost_ops; 73 74 if (!k->set_guest_notifiers) { 75 error_report("binding does not support guest notifiers"); 76 return -ENOSYS; 77 } 78 79 ret = vhost_ops->vhost_call(&s->dev, 80 VHOST_SCSI_GET_ABI_VERSION, &abi_version); 81 if (ret < 0) { 82 return -errno; 83 } 84 if (abi_version > VHOST_SCSI_ABI_VERSION) { 85 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 86 " %d is greater than vhost_scsi userspace supports: %d, please" 87 " upgrade your version of QEMU", abi_version, 88 VHOST_SCSI_ABI_VERSION); 89 return -ENOSYS; 90 } 91 92 ret = vhost_dev_enable_notifiers(&s->dev, vdev); 93 if (ret < 0) { 94 return ret; 95 } 96 97 s->dev.acked_features = vdev->guest_features; 98 ret = vhost_dev_start(&s->dev, vdev); 99 if (ret < 0) { 100 error_report("Error start vhost dev"); 101 goto err_notifiers; 102 } 103 104 ret = vhost_scsi_set_endpoint(s); 105 if (ret < 0) { 106 error_report("Error set vhost-scsi endpoint"); 107 goto err_vhost_stop; 108 } 109 110 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true); 111 if (ret < 0) { 112 error_report("Error binding guest notifier"); 113 goto err_endpoint; 114 } 115 116 /* guest_notifier_mask/pending not used yet, so just unmask 117 * everything here. virtio-pci will do the right thing by 118 * enabling/disabling irqfd. 119 */ 120 for (i = 0; i < s->dev.nvqs; i++) { 121 vhost_virtqueue_mask(&s->dev, vdev, i, false); 122 } 123 124 return ret; 125 126 err_endpoint: 127 vhost_scsi_clear_endpoint(s); 128 err_vhost_stop: 129 vhost_dev_stop(&s->dev, vdev); 130 err_notifiers: 131 vhost_dev_disable_notifiers(&s->dev, vdev); 132 return ret; 133 } 134 135 static void vhost_scsi_stop(VHostSCSI *s) 136 { 137 VirtIODevice *vdev = VIRTIO_DEVICE(s); 138 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 139 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 140 int ret = 0; 141 142 if (k->set_guest_notifiers) { 143 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false); 144 if (ret < 0) { 145 error_report("vhost guest notifier cleanup failed: %d", ret); 146 } 147 } 148 assert(ret >= 0); 149 150 vhost_scsi_clear_endpoint(s); 151 vhost_dev_stop(&s->dev, vdev); 152 vhost_dev_disable_notifiers(&s->dev, vdev); 153 } 154 155 static uint64_t vhost_scsi_get_features(VirtIODevice *vdev, 156 uint64_t features) 157 { 158 VHostSCSI *s = VHOST_SCSI(vdev); 159 160 return vhost_get_features(&s->dev, kernel_feature_bits, features); 161 } 162 163 static void vhost_scsi_set_config(VirtIODevice *vdev, 164 const uint8_t *config) 165 { 166 VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config; 167 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); 168 169 if ((uint32_t) virtio_ldl_p(vdev, &scsiconf->sense_size) != vs->sense_size || 170 (uint32_t) virtio_ldl_p(vdev, &scsiconf->cdb_size) != vs->cdb_size) { 171 error_report("vhost-scsi does not support changing the sense data and CDB sizes"); 172 exit(1); 173 } 174 } 175 176 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 177 { 178 VHostSCSI *s = (VHostSCSI *)vdev; 179 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 180 181 if (s->dev.started == start) { 182 return; 183 } 184 185 if (start) { 186 int ret; 187 188 ret = vhost_scsi_start(s); 189 if (ret < 0) { 190 error_report("virtio-scsi: unable to start vhost: %s", 191 strerror(-ret)); 192 193 /* There is no userspace virtio-scsi fallback so exit */ 194 exit(1); 195 } 196 } else { 197 vhost_scsi_stop(s); 198 } 199 } 200 201 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 202 { 203 } 204 205 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 206 { 207 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 208 VHostSCSI *s = VHOST_SCSI(dev); 209 Error *err = NULL; 210 int vhostfd = -1; 211 int ret; 212 213 if (!vs->conf.wwpn) { 214 error_setg(errp, "vhost-scsi: missing wwpn"); 215 return; 216 } 217 218 if (vs->conf.vhostfd) { 219 vhostfd = monitor_fd_param(cur_mon, vs->conf.vhostfd, &err); 220 if (vhostfd == -1) { 221 error_setg(errp, "vhost-scsi: unable to parse vhostfd: %s", 222 error_get_pretty(err)); 223 error_free(err); 224 return; 225 } 226 } else { 227 vhostfd = open("/dev/vhost-scsi", O_RDWR); 228 if (vhostfd < 0) { 229 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 230 strerror(errno)); 231 return; 232 } 233 } 234 235 virtio_scsi_common_realize(dev, &err, vhost_dummy_handle_output, 236 vhost_dummy_handle_output, 237 vhost_dummy_handle_output); 238 if (err != NULL) { 239 error_propagate(errp, err); 240 close(vhostfd); 241 return; 242 } 243 244 s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 245 s->dev.vqs = g_new(struct vhost_virtqueue, s->dev.nvqs); 246 s->dev.vq_index = 0; 247 s->dev.backend_features = 0; 248 249 ret = vhost_dev_init(&s->dev, (void *)(uintptr_t)vhostfd, 250 VHOST_BACKEND_TYPE_KERNEL); 251 if (ret < 0) { 252 error_setg(errp, "vhost-scsi: vhost initialization failed: %s", 253 strerror(-ret)); 254 return; 255 } 256 257 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 258 s->channel = 0; 259 s->lun = 0; 260 /* Note: we can also get the minimum tpgt from kernel */ 261 s->target = vs->conf.boot_tpgt; 262 263 error_setg(&s->migration_blocker, 264 "vhost-scsi does not support migration"); 265 migrate_add_blocker(s->migration_blocker); 266 } 267 268 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) 269 { 270 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 271 VHostSCSI *s = VHOST_SCSI(dev); 272 273 migrate_del_blocker(s->migration_blocker); 274 error_free(s->migration_blocker); 275 276 /* This will stop vhost backend. */ 277 vhost_scsi_set_status(vdev, 0); 278 279 g_free(s->dev.vqs); 280 281 virtio_scsi_common_unrealize(dev, errp); 282 } 283 284 /* 285 * Implementation of an interface to adjust firmware path 286 * for the bootindex property handling. 287 */ 288 static char *vhost_scsi_get_fw_dev_path(FWPathProvider *p, BusState *bus, 289 DeviceState *dev) 290 { 291 VHostSCSI *s = VHOST_SCSI(dev); 292 /* format: channel@channel/vhost-scsi@target,lun */ 293 return g_strdup_printf("channel@%x/%s@%x,%x", s->channel, 294 qdev_fw_name(dev), s->target, s->lun); 295 } 296 297 static Property vhost_scsi_properties[] = { 298 DEFINE_PROP_STRING("vhostfd", VHostSCSI, parent_obj.conf.vhostfd), 299 DEFINE_PROP_STRING("wwpn", VHostSCSI, parent_obj.conf.wwpn), 300 DEFINE_PROP_UINT32("boot_tpgt", VHostSCSI, parent_obj.conf.boot_tpgt, 0), 301 DEFINE_PROP_UINT32("num_queues", VHostSCSI, parent_obj.conf.num_queues, 1), 302 DEFINE_PROP_UINT32("max_sectors", VHostSCSI, parent_obj.conf.max_sectors, 303 0xFFFF), 304 DEFINE_PROP_UINT32("cmd_per_lun", VHostSCSI, parent_obj.conf.cmd_per_lun, 305 128), 306 DEFINE_PROP_END_OF_LIST(), 307 }; 308 309 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 310 { 311 DeviceClass *dc = DEVICE_CLASS(klass); 312 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 313 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 314 315 dc->props = vhost_scsi_properties; 316 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 317 vdc->realize = vhost_scsi_realize; 318 vdc->unrealize = vhost_scsi_unrealize; 319 vdc->get_features = vhost_scsi_get_features; 320 vdc->set_config = vhost_scsi_set_config; 321 vdc->set_status = vhost_scsi_set_status; 322 fwc->get_dev_path = vhost_scsi_get_fw_dev_path; 323 } 324 325 static void vhost_scsi_instance_init(Object *obj) 326 { 327 VHostSCSI *dev = VHOST_SCSI(obj); 328 329 device_add_bootindex_property(obj, &dev->bootindex, "bootindex", NULL, 330 DEVICE(dev), NULL); 331 } 332 333 static const TypeInfo vhost_scsi_info = { 334 .name = TYPE_VHOST_SCSI, 335 .parent = TYPE_VIRTIO_SCSI_COMMON, 336 .instance_size = sizeof(VHostSCSI), 337 .class_init = vhost_scsi_class_init, 338 .instance_init = vhost_scsi_instance_init, 339 .interfaces = (InterfaceInfo[]) { 340 { TYPE_FW_PATH_PROVIDER }, 341 { } 342 }, 343 }; 344 345 static void virtio_register_types(void) 346 { 347 type_register_static(&vhost_scsi_info); 348 } 349 350 type_init(virtio_register_types) 351