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 "qemu/osdep.h" 18 #include <linux/vhost.h> 19 #include <sys/ioctl.h> 20 #include "qapi/error.h" 21 #include "qemu/error-report.h" 22 #include "qemu/module.h" 23 #include "monitor/monitor.h" 24 #include "migration/blocker.h" 25 #include "hw/virtio/vhost-scsi.h" 26 #include "hw/virtio/vhost.h" 27 #include "hw/virtio/virtio-scsi.h" 28 #include "hw/virtio/virtio-bus.h" 29 #include "hw/virtio/virtio-access.h" 30 #include "hw/fw-path-provider.h" 31 #include "hw/qdev-properties.h" 32 #include "qemu/cutils.h" 33 #include "sysemu/sysemu.h" 34 35 /* Features supported by host kernel. */ 36 static const int kernel_feature_bits[] = { 37 VIRTIO_F_NOTIFY_ON_EMPTY, 38 VIRTIO_RING_F_INDIRECT_DESC, 39 VIRTIO_RING_F_EVENT_IDX, 40 VIRTIO_SCSI_F_HOTPLUG, 41 VIRTIO_F_RING_RESET, 42 VHOST_INVALID_FEATURE_BIT 43 }; 44 45 static int vhost_scsi_set_endpoint(VHostSCSI *s) 46 { 47 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 48 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 49 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 50 struct vhost_scsi_target backend; 51 int ret; 52 53 memset(&backend, 0, sizeof(backend)); 54 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 55 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend); 56 if (ret < 0) { 57 return -errno; 58 } 59 return 0; 60 } 61 62 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 63 { 64 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 65 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 66 struct vhost_scsi_target backend; 67 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 68 69 memset(&backend, 0, sizeof(backend)); 70 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 71 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend); 72 } 73 74 static int vhost_scsi_start(VHostSCSI *s) 75 { 76 int ret, abi_version; 77 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 78 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 79 80 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->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," 87 " please upgrade your version of QEMU", abi_version, 88 VHOST_SCSI_ABI_VERSION); 89 return -ENOSYS; 90 } 91 92 ret = vhost_scsi_common_start(vsc); 93 if (ret < 0) { 94 return ret; 95 } 96 97 ret = vhost_scsi_set_endpoint(s); 98 if (ret < 0) { 99 error_report("Error setting vhost-scsi endpoint"); 100 vhost_scsi_common_stop(vsc); 101 } 102 103 return ret; 104 } 105 106 static void vhost_scsi_stop(VHostSCSI *s) 107 { 108 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 109 110 vhost_scsi_clear_endpoint(s); 111 vhost_scsi_common_stop(vsc); 112 } 113 114 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 115 { 116 VHostSCSI *s = VHOST_SCSI(vdev); 117 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 118 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 119 120 if (!vdev->vm_running) { 121 start = false; 122 } 123 124 if (vhost_dev_is_started(&vsc->dev) == start) { 125 return; 126 } 127 128 if (start) { 129 int ret; 130 131 ret = vhost_scsi_start(s); 132 if (ret < 0) { 133 error_report("unable to start vhost-scsi: %s", strerror(-ret)); 134 exit(1); 135 } 136 } else { 137 vhost_scsi_stop(s); 138 } 139 } 140 141 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 142 { 143 } 144 145 static int vhost_scsi_pre_save(void *opaque) 146 { 147 VHostSCSICommon *vsc = opaque; 148 149 /* At this point, backend must be stopped, otherwise 150 * it might keep writing to memory. */ 151 assert(!vhost_dev_is_started(&vsc->dev)); 152 153 return 0; 154 } 155 156 static const VMStateDescription vmstate_virtio_vhost_scsi = { 157 .name = "virtio-vhost_scsi", 158 .minimum_version_id = 1, 159 .version_id = 1, 160 .fields = (VMStateField[]) { 161 VMSTATE_VIRTIO_DEVICE, 162 VMSTATE_END_OF_LIST() 163 }, 164 .pre_save = vhost_scsi_pre_save, 165 }; 166 167 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 168 { 169 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 170 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 171 Error *err = NULL; 172 int vhostfd = -1; 173 int ret; 174 struct vhost_virtqueue *vqs = NULL; 175 176 if (!vs->conf.wwpn) { 177 error_setg(errp, "vhost-scsi: missing wwpn"); 178 return; 179 } 180 181 if (vs->conf.vhostfd) { 182 vhostfd = monitor_fd_param(monitor_cur(), vs->conf.vhostfd, errp); 183 if (vhostfd == -1) { 184 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: "); 185 return; 186 } 187 } else { 188 vhostfd = open("/dev/vhost-scsi", O_RDWR); 189 if (vhostfd < 0) { 190 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 191 strerror(errno)); 192 return; 193 } 194 } 195 196 virtio_scsi_common_realize(dev, 197 vhost_dummy_handle_output, 198 vhost_dummy_handle_output, 199 vhost_dummy_handle_output, 200 &err); 201 if (err != NULL) { 202 error_propagate(errp, err); 203 goto close_fd; 204 } 205 206 if (!vsc->migratable) { 207 error_setg(&vsc->migration_blocker, 208 "vhost-scsi does not support migration in all cases. " 209 "When external environment supports it (Orchestrator migrates " 210 "target SCSI device state or use shared storage over network), " 211 "set 'migratable' property to true to enable migration."); 212 if (migrate_add_blocker(vsc->migration_blocker, errp) < 0) { 213 goto free_virtio; 214 } 215 } 216 217 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 218 vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); 219 vsc->dev.vqs = vqs; 220 vsc->dev.vq_index = 0; 221 vsc->dev.backend_features = 0; 222 223 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd, 224 VHOST_BACKEND_TYPE_KERNEL, 0, errp); 225 if (ret < 0) { 226 /* 227 * vhost_dev_init calls vhost_dev_cleanup on error, which closes 228 * vhostfd, don't double close it. 229 */ 230 vhostfd = -1; 231 goto free_vqs; 232 } 233 234 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 235 vsc->channel = 0; 236 vsc->lun = 0; 237 /* Note: we can also get the minimum tpgt from kernel */ 238 vsc->target = vs->conf.boot_tpgt; 239 240 return; 241 242 free_vqs: 243 g_free(vqs); 244 if (!vsc->migratable) { 245 migrate_del_blocker(vsc->migration_blocker); 246 } 247 free_virtio: 248 error_free(vsc->migration_blocker); 249 virtio_scsi_common_unrealize(dev); 250 close_fd: 251 if (vhostfd >= 0) { 252 close(vhostfd); 253 } 254 return; 255 } 256 257 static void vhost_scsi_unrealize(DeviceState *dev) 258 { 259 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 260 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 261 struct vhost_virtqueue *vqs = vsc->dev.vqs; 262 263 if (!vsc->migratable) { 264 migrate_del_blocker(vsc->migration_blocker); 265 error_free(vsc->migration_blocker); 266 } 267 268 /* This will stop vhost backend. */ 269 vhost_scsi_set_status(vdev, 0); 270 271 vhost_dev_cleanup(&vsc->dev); 272 g_free(vqs); 273 274 virtio_scsi_common_unrealize(dev); 275 } 276 277 static struct vhost_dev *vhost_scsi_get_vhost(VirtIODevice *vdev) 278 { 279 VHostSCSI *s = VHOST_SCSI(vdev); 280 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 281 return &vsc->dev; 282 } 283 284 static Property vhost_scsi_properties[] = { 285 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd), 286 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn), 287 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 288 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 289 VIRTIO_SCSI_AUTO_NUM_QUEUES), 290 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 291 128), 292 DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSICommon, conf.seg_max_adjust, 293 true), 294 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 295 0xFFFF), 296 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 297 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 298 VIRTIO_SCSI_F_T10_PI, 299 false), 300 DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false), 301 DEFINE_PROP_END_OF_LIST(), 302 }; 303 304 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 305 { 306 DeviceClass *dc = DEVICE_CLASS(klass); 307 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 308 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 309 310 device_class_set_props(dc, vhost_scsi_properties); 311 dc->vmsd = &vmstate_virtio_vhost_scsi; 312 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 313 vdc->realize = vhost_scsi_realize; 314 vdc->unrealize = vhost_scsi_unrealize; 315 vdc->get_features = vhost_scsi_common_get_features; 316 vdc->set_config = vhost_scsi_common_set_config; 317 vdc->set_status = vhost_scsi_set_status; 318 vdc->get_vhost = vhost_scsi_get_vhost; 319 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 320 } 321 322 static void vhost_scsi_instance_init(Object *obj) 323 { 324 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 325 326 vsc->feature_bits = kernel_feature_bits; 327 328 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 329 DEVICE(vsc)); 330 } 331 332 static const TypeInfo vhost_scsi_info = { 333 .name = TYPE_VHOST_SCSI, 334 .parent = TYPE_VHOST_SCSI_COMMON, 335 .instance_size = sizeof(VHostSCSI), 336 .class_init = vhost_scsi_class_init, 337 .instance_init = vhost_scsi_instance_init, 338 .interfaces = (InterfaceInfo[]) { 339 { TYPE_FW_PATH_PROVIDER }, 340 { } 341 }, 342 }; 343 344 static void virtio_register_types(void) 345 { 346 type_register_static(&vhost_scsi_info); 347 } 348 349 type_init(virtio_register_types) 350