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/queue.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 "qemu/cutils.h" 32 33 /* Features supported by host kernel. */ 34 static const int kernel_feature_bits[] = { 35 VIRTIO_F_NOTIFY_ON_EMPTY, 36 VIRTIO_RING_F_INDIRECT_DESC, 37 VIRTIO_RING_F_EVENT_IDX, 38 VIRTIO_SCSI_F_HOTPLUG, 39 VHOST_INVALID_FEATURE_BIT 40 }; 41 42 static int vhost_scsi_set_endpoint(VHostSCSI *s) 43 { 44 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 45 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 46 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 47 struct vhost_scsi_target backend; 48 int ret; 49 50 memset(&backend, 0, sizeof(backend)); 51 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 52 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend); 53 if (ret < 0) { 54 return -errno; 55 } 56 return 0; 57 } 58 59 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 60 { 61 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 62 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 63 struct vhost_scsi_target backend; 64 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 65 66 memset(&backend, 0, sizeof(backend)); 67 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 68 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend); 69 } 70 71 static int vhost_scsi_start(VHostSCSI *s) 72 { 73 int ret, abi_version; 74 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 75 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 76 77 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version); 78 if (ret < 0) { 79 return -errno; 80 } 81 if (abi_version > VHOST_SCSI_ABI_VERSION) { 82 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 83 " %d is greater than vhost_scsi userspace supports: %d," 84 " please upgrade your version of QEMU", abi_version, 85 VHOST_SCSI_ABI_VERSION); 86 return -ENOSYS; 87 } 88 89 ret = vhost_scsi_common_start(vsc); 90 if (ret < 0) { 91 return ret; 92 } 93 94 ret = vhost_scsi_set_endpoint(s); 95 if (ret < 0) { 96 error_report("Error setting vhost-scsi endpoint"); 97 vhost_scsi_common_stop(vsc); 98 } 99 100 return ret; 101 } 102 103 static void vhost_scsi_stop(VHostSCSI *s) 104 { 105 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 106 107 vhost_scsi_clear_endpoint(s); 108 vhost_scsi_common_stop(vsc); 109 } 110 111 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 112 { 113 VHostSCSI *s = VHOST_SCSI(vdev); 114 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 115 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 116 117 if (!vdev->vm_running) { 118 start = false; 119 } 120 121 if (vsc->dev.started == start) { 122 return; 123 } 124 125 if (start) { 126 int ret; 127 128 ret = vhost_scsi_start(s); 129 if (ret < 0) { 130 error_report("unable to start vhost-scsi: %s", strerror(-ret)); 131 exit(1); 132 } 133 } else { 134 vhost_scsi_stop(s); 135 } 136 } 137 138 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 139 { 140 } 141 142 static int vhost_scsi_pre_save(void *opaque) 143 { 144 VHostSCSICommon *vsc = opaque; 145 146 /* At this point, backend must be stopped, otherwise 147 * it might keep writing to memory. */ 148 assert(!vsc->dev.started); 149 150 return 0; 151 } 152 153 static const VMStateDescription vmstate_virtio_vhost_scsi = { 154 .name = "virtio-vhost_scsi", 155 .minimum_version_id = 1, 156 .version_id = 1, 157 .fields = (VMStateField[]) { 158 VMSTATE_VIRTIO_DEVICE, 159 VMSTATE_END_OF_LIST() 160 }, 161 .pre_save = vhost_scsi_pre_save, 162 }; 163 164 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 165 { 166 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 167 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 168 Error *err = NULL; 169 int vhostfd = -1; 170 int ret; 171 172 if (!vs->conf.wwpn) { 173 error_setg(errp, "vhost-scsi: missing wwpn"); 174 return; 175 } 176 177 if (vs->conf.vhostfd) { 178 vhostfd = monitor_fd_param(cur_mon, vs->conf.vhostfd, errp); 179 if (vhostfd == -1) { 180 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: "); 181 return; 182 } 183 } else { 184 vhostfd = open("/dev/vhost-scsi", O_RDWR); 185 if (vhostfd < 0) { 186 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 187 strerror(errno)); 188 return; 189 } 190 } 191 192 virtio_scsi_common_realize(dev, 193 vhost_dummy_handle_output, 194 vhost_dummy_handle_output, 195 vhost_dummy_handle_output, 196 &err); 197 if (err != NULL) { 198 error_propagate(errp, err); 199 goto close_fd; 200 } 201 202 if (!vsc->migratable) { 203 error_setg(&vsc->migration_blocker, 204 "vhost-scsi does not support migration in all cases. " 205 "When external environment supports it (Orchestrator migrates " 206 "target SCSI device state or use shared storage over network), " 207 "set 'migratable' property to true to enable migration."); 208 migrate_add_blocker(vsc->migration_blocker, &err); 209 if (err) { 210 error_propagate(errp, err); 211 error_free(vsc->migration_blocker); 212 goto close_fd; 213 } 214 } 215 216 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 217 vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); 218 vsc->dev.vq_index = 0; 219 vsc->dev.backend_features = 0; 220 221 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd, 222 VHOST_BACKEND_TYPE_KERNEL, 0); 223 if (ret < 0) { 224 error_setg(errp, "vhost-scsi: vhost initialization failed: %s", 225 strerror(-ret)); 226 goto free_vqs; 227 } 228 229 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 230 vsc->channel = 0; 231 vsc->lun = 0; 232 /* Note: we can also get the minimum tpgt from kernel */ 233 vsc->target = vs->conf.boot_tpgt; 234 235 return; 236 237 free_vqs: 238 if (!vsc->migratable) { 239 migrate_del_blocker(vsc->migration_blocker); 240 } 241 g_free(vsc->dev.vqs); 242 close_fd: 243 close(vhostfd); 244 return; 245 } 246 247 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) 248 { 249 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 250 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 251 struct vhost_virtqueue *vqs = vsc->dev.vqs; 252 253 if (!vsc->migratable) { 254 migrate_del_blocker(vsc->migration_blocker); 255 error_free(vsc->migration_blocker); 256 } 257 258 /* This will stop vhost backend. */ 259 vhost_scsi_set_status(vdev, 0); 260 261 vhost_dev_cleanup(&vsc->dev); 262 g_free(vqs); 263 264 virtio_scsi_common_unrealize(dev, errp); 265 } 266 267 static Property vhost_scsi_properties[] = { 268 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd), 269 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn), 270 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 271 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1), 272 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 273 128), 274 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 275 0xFFFF), 276 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 277 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 278 VIRTIO_SCSI_F_T10_PI, 279 false), 280 DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false), 281 DEFINE_PROP_END_OF_LIST(), 282 }; 283 284 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 285 { 286 DeviceClass *dc = DEVICE_CLASS(klass); 287 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 288 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 289 290 dc->props = vhost_scsi_properties; 291 dc->vmsd = &vmstate_virtio_vhost_scsi; 292 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 293 vdc->realize = vhost_scsi_realize; 294 vdc->unrealize = vhost_scsi_unrealize; 295 vdc->get_features = vhost_scsi_common_get_features; 296 vdc->set_config = vhost_scsi_common_set_config; 297 vdc->set_status = vhost_scsi_set_status; 298 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 299 } 300 301 static void vhost_scsi_instance_init(Object *obj) 302 { 303 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 304 305 vsc->feature_bits = kernel_feature_bits; 306 307 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 308 DEVICE(vsc), NULL); 309 } 310 311 static const TypeInfo vhost_scsi_info = { 312 .name = TYPE_VHOST_SCSI, 313 .parent = TYPE_VHOST_SCSI_COMMON, 314 .instance_size = sizeof(VHostSCSI), 315 .class_init = vhost_scsi_class_init, 316 .instance_init = vhost_scsi_instance_init, 317 .interfaces = (InterfaceInfo[]) { 318 { TYPE_FW_PATH_PROVIDER }, 319 { } 320 }, 321 }; 322 323 static void virtio_register_types(void) 324 { 325 type_register_static(&vhost_scsi_info); 326 } 327 328 type_init(virtio_register_types) 329