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 #include "linux/vhost.h" 30 31 /* Features supported by host kernel. */ 32 static const int kernel_feature_bits[] = { 33 VIRTIO_F_NOTIFY_ON_EMPTY, 34 VIRTIO_RING_F_INDIRECT_DESC, 35 VIRTIO_RING_F_EVENT_IDX, 36 VIRTIO_SCSI_F_HOTPLUG, 37 VHOST_INVALID_FEATURE_BIT 38 }; 39 40 static int vhost_scsi_set_endpoint(VHostSCSI *s) 41 { 42 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 43 const VhostOps *vhost_ops = s->dev.vhost_ops; 44 struct vhost_scsi_target backend; 45 int ret; 46 47 memset(&backend, 0, sizeof(backend)); 48 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 49 ret = vhost_ops->vhost_scsi_set_endpoint(&s->dev, &backend); 50 if (ret < 0) { 51 return -errno; 52 } 53 return 0; 54 } 55 56 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 57 { 58 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 59 struct vhost_scsi_target backend; 60 const VhostOps *vhost_ops = s->dev.vhost_ops; 61 62 memset(&backend, 0, sizeof(backend)); 63 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 64 vhost_ops->vhost_scsi_clear_endpoint(&s->dev, &backend); 65 } 66 67 static int vhost_scsi_start(VHostSCSI *s) 68 { 69 int ret, abi_version, i; 70 VirtIODevice *vdev = VIRTIO_DEVICE(s); 71 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 72 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 73 const VhostOps *vhost_ops = s->dev.vhost_ops; 74 75 if (!k->set_guest_notifiers) { 76 error_report("binding does not support guest notifiers"); 77 return -ENOSYS; 78 } 79 80 ret = vhost_ops->vhost_scsi_get_abi_version(&s->dev, &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, s->dev.vq_index + 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 Error **errp) 158 { 159 VHostSCSI *s = VHOST_SCSI(vdev); 160 161 return vhost_get_features(&s->dev, kernel_feature_bits, features); 162 } 163 164 static void vhost_scsi_set_config(VirtIODevice *vdev, 165 const uint8_t *config) 166 { 167 VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config; 168 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); 169 170 if ((uint32_t) virtio_ldl_p(vdev, &scsiconf->sense_size) != vs->sense_size || 171 (uint32_t) virtio_ldl_p(vdev, &scsiconf->cdb_size) != vs->cdb_size) { 172 error_report("vhost-scsi does not support changing the sense data and CDB sizes"); 173 exit(1); 174 } 175 } 176 177 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 178 { 179 VHostSCSI *s = (VHostSCSI *)vdev; 180 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 181 182 if (s->dev.started == start) { 183 return; 184 } 185 186 if (start) { 187 int ret; 188 189 ret = vhost_scsi_start(s); 190 if (ret < 0) { 191 error_report("virtio-scsi: unable to start vhost: %s", 192 strerror(-ret)); 193 194 /* There is no userspace virtio-scsi fallback so exit */ 195 exit(1); 196 } 197 } else { 198 vhost_scsi_stop(s); 199 } 200 } 201 202 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 203 { 204 } 205 206 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 207 { 208 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 209 VHostSCSI *s = VHOST_SCSI(dev); 210 Error *err = NULL; 211 int vhostfd = -1; 212 int ret; 213 214 if (!vs->conf.wwpn) { 215 error_setg(errp, "vhost-scsi: missing wwpn"); 216 return; 217 } 218 219 if (vs->conf.vhostfd) { 220 vhostfd = monitor_fd_param(cur_mon, vs->conf.vhostfd, &err); 221 if (vhostfd == -1) { 222 error_setg(errp, "vhost-scsi: unable to parse vhostfd: %s", 223 error_get_pretty(err)); 224 error_free(err); 225 return; 226 } 227 } else { 228 vhostfd = open("/dev/vhost-scsi", O_RDWR); 229 if (vhostfd < 0) { 230 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 231 strerror(errno)); 232 return; 233 } 234 } 235 236 virtio_scsi_common_realize(dev, &err, vhost_dummy_handle_output, 237 vhost_dummy_handle_output, 238 vhost_dummy_handle_output); 239 if (err != NULL) { 240 error_propagate(errp, err); 241 close(vhostfd); 242 return; 243 } 244 245 s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 246 s->dev.vqs = g_new(struct vhost_virtqueue, s->dev.nvqs); 247 s->dev.vq_index = 0; 248 s->dev.backend_features = 0; 249 250 ret = vhost_dev_init(&s->dev, (void *)(uintptr_t)vhostfd, 251 VHOST_BACKEND_TYPE_KERNEL); 252 if (ret < 0) { 253 error_setg(errp, "vhost-scsi: vhost initialization failed: %s", 254 strerror(-ret)); 255 return; 256 } 257 258 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 259 s->channel = 0; 260 s->lun = 0; 261 /* Note: we can also get the minimum tpgt from kernel */ 262 s->target = vs->conf.boot_tpgt; 263 264 error_setg(&s->migration_blocker, 265 "vhost-scsi does not support migration"); 266 migrate_add_blocker(s->migration_blocker); 267 } 268 269 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) 270 { 271 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 272 VHostSCSI *s = VHOST_SCSI(dev); 273 274 migrate_del_blocker(s->migration_blocker); 275 error_free(s->migration_blocker); 276 277 /* This will stop vhost backend. */ 278 vhost_scsi_set_status(vdev, 0); 279 280 vhost_dev_cleanup(&s->dev); 281 g_free(s->dev.vqs); 282 283 virtio_scsi_common_unrealize(dev, errp); 284 } 285 286 /* 287 * Implementation of an interface to adjust firmware path 288 * for the bootindex property handling. 289 */ 290 static char *vhost_scsi_get_fw_dev_path(FWPathProvider *p, BusState *bus, 291 DeviceState *dev) 292 { 293 VHostSCSI *s = VHOST_SCSI(dev); 294 /* format: channel@channel/vhost-scsi@target,lun */ 295 return g_strdup_printf("/channel@%x/%s@%x,%x", s->channel, 296 qdev_fw_name(dev), s->target, s->lun); 297 } 298 299 static Property vhost_scsi_properties[] = { 300 DEFINE_PROP_STRING("vhostfd", VHostSCSI, parent_obj.conf.vhostfd), 301 DEFINE_PROP_STRING("wwpn", VHostSCSI, parent_obj.conf.wwpn), 302 DEFINE_PROP_UINT32("boot_tpgt", VHostSCSI, parent_obj.conf.boot_tpgt, 0), 303 DEFINE_PROP_UINT32("num_queues", VHostSCSI, parent_obj.conf.num_queues, 1), 304 DEFINE_PROP_UINT32("max_sectors", VHostSCSI, parent_obj.conf.max_sectors, 305 0xFFFF), 306 DEFINE_PROP_UINT32("cmd_per_lun", VHostSCSI, parent_obj.conf.cmd_per_lun, 307 128), 308 DEFINE_PROP_END_OF_LIST(), 309 }; 310 311 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 312 { 313 DeviceClass *dc = DEVICE_CLASS(klass); 314 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 315 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 316 317 dc->props = vhost_scsi_properties; 318 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 319 vdc->realize = vhost_scsi_realize; 320 vdc->unrealize = vhost_scsi_unrealize; 321 vdc->get_features = vhost_scsi_get_features; 322 vdc->set_config = vhost_scsi_set_config; 323 vdc->set_status = vhost_scsi_set_status; 324 fwc->get_dev_path = vhost_scsi_get_fw_dev_path; 325 } 326 327 static void vhost_scsi_instance_init(Object *obj) 328 { 329 VHostSCSI *dev = VHOST_SCSI(obj); 330 331 device_add_bootindex_property(obj, &dev->bootindex, "bootindex", NULL, 332 DEVICE(dev), NULL); 333 } 334 335 static const TypeInfo vhost_scsi_info = { 336 .name = TYPE_VHOST_SCSI, 337 .parent = TYPE_VIRTIO_SCSI_COMMON, 338 .instance_size = sizeof(VHostSCSI), 339 .class_init = vhost_scsi_class_init, 340 .instance_init = vhost_scsi_instance_init, 341 .interfaces = (InterfaceInfo[]) { 342 { TYPE_FW_PATH_PROVIDER }, 343 { } 344 }, 345 }; 346 347 static void virtio_register_types(void) 348 { 349 type_register_static(&vhost_scsi_info); 350 } 351 352 type_init(virtio_register_types) 353