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 VHOST_INVALID_FEATURE_BIT 42 }; 43 44 static int vhost_scsi_set_endpoint(VHostSCSI *s) 45 { 46 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 47 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 48 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 49 struct vhost_scsi_target backend; 50 int ret; 51 52 memset(&backend, 0, sizeof(backend)); 53 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 54 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend); 55 if (ret < 0) { 56 return -errno; 57 } 58 return 0; 59 } 60 61 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 62 { 63 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 64 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 65 struct vhost_scsi_target backend; 66 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 67 68 memset(&backend, 0, sizeof(backend)); 69 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 70 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend); 71 } 72 73 static int vhost_scsi_start(VHostSCSI *s) 74 { 75 int ret, abi_version; 76 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 77 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 78 79 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version); 80 if (ret < 0) { 81 return -errno; 82 } 83 if (abi_version > VHOST_SCSI_ABI_VERSION) { 84 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 85 " %d is greater than vhost_scsi userspace supports: %d," 86 " please upgrade your version of QEMU", abi_version, 87 VHOST_SCSI_ABI_VERSION); 88 return -ENOSYS; 89 } 90 91 ret = vhost_scsi_common_start(vsc); 92 if (ret < 0) { 93 return ret; 94 } 95 96 ret = vhost_scsi_set_endpoint(s); 97 if (ret < 0) { 98 error_report("Error setting vhost-scsi endpoint"); 99 vhost_scsi_common_stop(vsc); 100 } 101 102 return ret; 103 } 104 105 static void vhost_scsi_stop(VHostSCSI *s) 106 { 107 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 108 109 vhost_scsi_clear_endpoint(s); 110 vhost_scsi_common_stop(vsc); 111 } 112 113 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 114 { 115 VHostSCSI *s = VHOST_SCSI(vdev); 116 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 117 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 118 119 if (!vdev->vm_running) { 120 start = false; 121 } 122 123 if (vsc->dev.started == start) { 124 return; 125 } 126 127 if (start) { 128 int ret; 129 130 ret = vhost_scsi_start(s); 131 if (ret < 0) { 132 error_report("unable to start vhost-scsi: %s", strerror(-ret)); 133 exit(1); 134 } 135 } else { 136 vhost_scsi_stop(s); 137 } 138 } 139 140 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 141 { 142 } 143 144 static int vhost_scsi_pre_save(void *opaque) 145 { 146 VHostSCSICommon *vsc = opaque; 147 148 /* At this point, backend must be stopped, otherwise 149 * it might keep writing to memory. */ 150 assert(!vsc->dev.started); 151 152 return 0; 153 } 154 155 static const VMStateDescription vmstate_virtio_vhost_scsi = { 156 .name = "virtio-vhost_scsi", 157 .minimum_version_id = 1, 158 .version_id = 1, 159 .fields = (VMStateField[]) { 160 VMSTATE_VIRTIO_DEVICE, 161 VMSTATE_END_OF_LIST() 162 }, 163 .pre_save = vhost_scsi_pre_save, 164 }; 165 166 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 167 { 168 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 169 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 170 Error *err = NULL; 171 int vhostfd = -1; 172 int ret; 173 struct vhost_virtqueue *vqs = NULL; 174 175 if (!vs->conf.wwpn) { 176 error_setg(errp, "vhost-scsi: missing wwpn"); 177 return; 178 } 179 180 if (vs->conf.vhostfd) { 181 vhostfd = monitor_fd_param(monitor_cur(), vs->conf.vhostfd, errp); 182 if (vhostfd == -1) { 183 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: "); 184 return; 185 } 186 } else { 187 vhostfd = open("/dev/vhost-scsi", O_RDWR); 188 if (vhostfd < 0) { 189 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 190 strerror(errno)); 191 return; 192 } 193 } 194 195 virtio_scsi_common_realize(dev, 196 vhost_dummy_handle_output, 197 vhost_dummy_handle_output, 198 vhost_dummy_handle_output, 199 &err); 200 if (err != NULL) { 201 error_propagate(errp, err); 202 goto close_fd; 203 } 204 205 if (!vsc->migratable) { 206 error_setg(&vsc->migration_blocker, 207 "vhost-scsi does not support migration in all cases. " 208 "When external environment supports it (Orchestrator migrates " 209 "target SCSI device state or use shared storage over network), " 210 "set 'migratable' property to true to enable migration."); 211 if (migrate_add_blocker(vsc->migration_blocker, errp) < 0) { 212 goto free_virtio; 213 } 214 } 215 216 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 217 vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); 218 vsc->dev.vqs = vqs; 219 vsc->dev.vq_index = 0; 220 vsc->dev.backend_features = 0; 221 222 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd, 223 VHOST_BACKEND_TYPE_KERNEL, 0, errp); 224 if (ret < 0) { 225 /* 226 * vhost_dev_init calls vhost_dev_cleanup on error, which closes 227 * vhostfd, don't double close it. 228 */ 229 vhostfd = -1; 230 goto free_vqs; 231 } 232 233 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 234 vsc->channel = 0; 235 vsc->lun = 0; 236 /* Note: we can also get the minimum tpgt from kernel */ 237 vsc->target = vs->conf.boot_tpgt; 238 239 return; 240 241 free_vqs: 242 g_free(vqs); 243 if (!vsc->migratable) { 244 migrate_del_blocker(vsc->migration_blocker); 245 } 246 free_virtio: 247 error_free(vsc->migration_blocker); 248 virtio_scsi_common_unrealize(dev); 249 close_fd: 250 if (vhostfd >= 0) { 251 close(vhostfd); 252 } 253 return; 254 } 255 256 static void vhost_scsi_unrealize(DeviceState *dev) 257 { 258 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 259 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 260 struct vhost_virtqueue *vqs = vsc->dev.vqs; 261 262 if (!vsc->migratable) { 263 migrate_del_blocker(vsc->migration_blocker); 264 error_free(vsc->migration_blocker); 265 } 266 267 /* This will stop vhost backend. */ 268 vhost_scsi_set_status(vdev, 0); 269 270 vhost_dev_cleanup(&vsc->dev); 271 g_free(vqs); 272 273 virtio_scsi_common_unrealize(dev); 274 } 275 276 static struct vhost_dev *vhost_scsi_get_vhost(VirtIODevice *vdev) 277 { 278 VHostSCSI *s = VHOST_SCSI(vdev); 279 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 280 return &vsc->dev; 281 } 282 283 static Property vhost_scsi_properties[] = { 284 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd), 285 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn), 286 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 287 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 288 VIRTIO_SCSI_AUTO_NUM_QUEUES), 289 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 290 128), 291 DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSICommon, conf.seg_max_adjust, 292 true), 293 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 294 0xFFFF), 295 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 296 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 297 VIRTIO_SCSI_F_T10_PI, 298 false), 299 DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false), 300 DEFINE_PROP_END_OF_LIST(), 301 }; 302 303 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 304 { 305 DeviceClass *dc = DEVICE_CLASS(klass); 306 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 307 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 308 309 device_class_set_props(dc, vhost_scsi_properties); 310 dc->vmsd = &vmstate_virtio_vhost_scsi; 311 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 312 vdc->realize = vhost_scsi_realize; 313 vdc->unrealize = vhost_scsi_unrealize; 314 vdc->get_features = vhost_scsi_common_get_features; 315 vdc->set_config = vhost_scsi_common_set_config; 316 vdc->set_status = vhost_scsi_set_status; 317 vdc->get_vhost = vhost_scsi_get_vhost; 318 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 319 } 320 321 static void vhost_scsi_instance_init(Object *obj) 322 { 323 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 324 325 vsc->feature_bits = kernel_feature_bits; 326 327 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 328 DEVICE(vsc)); 329 } 330 331 static const TypeInfo vhost_scsi_info = { 332 .name = TYPE_VHOST_SCSI, 333 .parent = TYPE_VHOST_SCSI_COMMON, 334 .instance_size = sizeof(VHostSCSI), 335 .class_init = vhost_scsi_class_init, 336 .instance_init = vhost_scsi_instance_init, 337 .interfaces = (InterfaceInfo[]) { 338 { TYPE_FW_PATH_PROVIDER }, 339 { } 340 }, 341 }; 342 343 static void virtio_register_types(void) 344 { 345 type_register_static(&vhost_scsi_info); 346 } 347 348 type_init(virtio_register_types) 349