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/queue.h" 20 #include "monitor/monitor.h" 21 #include "migration/migration.h" 22 #include "hw/virtio/vhost-scsi.h" 23 #include "hw/virtio/vhost.h" 24 #include "hw/virtio/virtio-scsi.h" 25 #include "hw/virtio/virtio-bus.h" 26 27 static int vhost_scsi_set_endpoint(VHostSCSI *s) 28 { 29 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 30 struct vhost_scsi_target backend; 31 int ret; 32 33 memset(&backend, 0, sizeof(backend)); 34 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 35 ret = ioctl(s->dev.control, VHOST_SCSI_SET_ENDPOINT, &backend); 36 if (ret < 0) { 37 return -errno; 38 } 39 return 0; 40 } 41 42 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 43 { 44 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 45 struct vhost_scsi_target backend; 46 47 memset(&backend, 0, sizeof(backend)); 48 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 49 ioctl(s->dev.control, VHOST_SCSI_CLEAR_ENDPOINT, &backend); 50 } 51 52 static int vhost_scsi_start(VHostSCSI *s) 53 { 54 int ret, abi_version, i; 55 VirtIODevice *vdev = VIRTIO_DEVICE(s); 56 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 57 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 58 59 if (!k->set_guest_notifiers) { 60 error_report("binding does not support guest notifiers"); 61 return -ENOSYS; 62 } 63 64 ret = ioctl(s->dev.control, VHOST_SCSI_GET_ABI_VERSION, &abi_version); 65 if (ret < 0) { 66 return -errno; 67 } 68 if (abi_version > VHOST_SCSI_ABI_VERSION) { 69 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 70 " %d is greater than vhost_scsi userspace supports: %d, please" 71 " upgrade your version of QEMU\n", abi_version, 72 VHOST_SCSI_ABI_VERSION); 73 return -ENOSYS; 74 } 75 76 ret = vhost_dev_enable_notifiers(&s->dev, vdev); 77 if (ret < 0) { 78 return ret; 79 } 80 81 s->dev.acked_features = vdev->guest_features; 82 ret = vhost_dev_start(&s->dev, vdev); 83 if (ret < 0) { 84 error_report("Error start vhost dev"); 85 goto err_notifiers; 86 } 87 88 ret = vhost_scsi_set_endpoint(s); 89 if (ret < 0) { 90 error_report("Error set vhost-scsi endpoint"); 91 goto err_vhost_stop; 92 } 93 94 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true); 95 if (ret < 0) { 96 error_report("Error binding guest notifier"); 97 goto err_endpoint; 98 } 99 100 /* guest_notifier_mask/pending not used yet, so just unmask 101 * everything here. virtio-pci will do the right thing by 102 * enabling/disabling irqfd. 103 */ 104 for (i = 0; i < s->dev.nvqs; i++) { 105 vhost_virtqueue_mask(&s->dev, vdev, i, false); 106 } 107 108 return ret; 109 110 err_endpoint: 111 vhost_scsi_clear_endpoint(s); 112 err_vhost_stop: 113 vhost_dev_stop(&s->dev, vdev); 114 err_notifiers: 115 vhost_dev_disable_notifiers(&s->dev, vdev); 116 return ret; 117 } 118 119 static void vhost_scsi_stop(VHostSCSI *s) 120 { 121 VirtIODevice *vdev = VIRTIO_DEVICE(s); 122 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 123 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 124 int ret = 0; 125 126 if (k->set_guest_notifiers) { 127 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false); 128 if (ret < 0) { 129 error_report("vhost guest notifier cleanup failed: %d\n", ret); 130 } 131 } 132 assert(ret >= 0); 133 134 vhost_scsi_clear_endpoint(s); 135 vhost_dev_stop(&s->dev, vdev); 136 vhost_dev_disable_notifiers(&s->dev, vdev); 137 } 138 139 static uint32_t vhost_scsi_get_features(VirtIODevice *vdev, 140 uint32_t features) 141 { 142 VHostSCSI *s = VHOST_SCSI(vdev); 143 144 /* Clear features not supported by host kernel. */ 145 if (!(s->dev.features & (1 << VIRTIO_F_NOTIFY_ON_EMPTY))) { 146 features &= ~(1 << VIRTIO_F_NOTIFY_ON_EMPTY); 147 } 148 if (!(s->dev.features & (1 << VIRTIO_RING_F_INDIRECT_DESC))) { 149 features &= ~(1 << VIRTIO_RING_F_INDIRECT_DESC); 150 } 151 if (!(s->dev.features & (1 << VIRTIO_RING_F_EVENT_IDX))) { 152 features &= ~(1 << VIRTIO_RING_F_EVENT_IDX); 153 } 154 if (!(s->dev.features & (1 << VIRTIO_SCSI_F_HOTPLUG))) { 155 features &= ~(1 << VIRTIO_SCSI_F_HOTPLUG); 156 } 157 158 return features; 159 } 160 161 static void vhost_scsi_set_config(VirtIODevice *vdev, 162 const uint8_t *config) 163 { 164 VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config; 165 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); 166 167 if ((uint32_t) ldl_p(&scsiconf->sense_size) != vs->sense_size || 168 (uint32_t) ldl_p(&scsiconf->cdb_size) != vs->cdb_size) { 169 error_report("vhost-scsi does not support changing the sense data and CDB sizes"); 170 exit(1); 171 } 172 } 173 174 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 175 { 176 VHostSCSI *s = (VHostSCSI *)vdev; 177 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 178 179 if (s->dev.started == start) { 180 return; 181 } 182 183 if (start) { 184 int ret; 185 186 ret = vhost_scsi_start(s); 187 if (ret < 0) { 188 error_report("virtio-scsi: unable to start vhost: %s\n", 189 strerror(-ret)); 190 191 /* There is no userspace virtio-scsi fallback so exit */ 192 exit(1); 193 } 194 } else { 195 vhost_scsi_stop(s); 196 } 197 } 198 199 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 200 { 201 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 202 VHostSCSI *s = VHOST_SCSI(dev); 203 Error *err = NULL; 204 int vhostfd = -1; 205 int ret; 206 207 if (!vs->conf.wwpn) { 208 error_setg(errp, "vhost-scsi: missing wwpn"); 209 return; 210 } 211 212 if (vs->conf.vhostfd) { 213 vhostfd = monitor_handle_fd_param(cur_mon, vs->conf.vhostfd); 214 if (vhostfd == -1) { 215 error_setg(errp, "vhost-scsi: unable to parse vhostfd"); 216 return; 217 } 218 } 219 220 virtio_scsi_common_realize(dev, &err); 221 if (err != NULL) { 222 error_propagate(errp, err); 223 return; 224 } 225 226 s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 227 s->dev.vqs = g_new(struct vhost_virtqueue, s->dev.nvqs); 228 s->dev.vq_index = 0; 229 230 ret = vhost_dev_init(&s->dev, vhostfd, "/dev/vhost-scsi", true); 231 if (ret < 0) { 232 error_setg(errp, "vhost-scsi: vhost initialization failed: %s", 233 strerror(-ret)); 234 return; 235 } 236 s->dev.backend_features = 0; 237 238 error_setg(&s->migration_blocker, 239 "vhost-scsi does not support migration"); 240 migrate_add_blocker(s->migration_blocker); 241 } 242 243 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) 244 { 245 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 246 VHostSCSI *s = VHOST_SCSI(dev); 247 248 migrate_del_blocker(s->migration_blocker); 249 error_free(s->migration_blocker); 250 251 /* This will stop vhost backend. */ 252 vhost_scsi_set_status(vdev, 0); 253 254 g_free(s->dev.vqs); 255 256 virtio_scsi_common_unrealize(dev, errp); 257 } 258 259 static Property vhost_scsi_properties[] = { 260 DEFINE_VHOST_SCSI_PROPERTIES(VHostSCSI, parent_obj.conf), 261 DEFINE_PROP_END_OF_LIST(), 262 }; 263 264 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 265 { 266 DeviceClass *dc = DEVICE_CLASS(klass); 267 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 268 269 dc->props = vhost_scsi_properties; 270 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 271 vdc->realize = vhost_scsi_realize; 272 vdc->unrealize = vhost_scsi_unrealize; 273 vdc->get_features = vhost_scsi_get_features; 274 vdc->set_config = vhost_scsi_set_config; 275 vdc->set_status = vhost_scsi_set_status; 276 } 277 278 static const TypeInfo vhost_scsi_info = { 279 .name = TYPE_VHOST_SCSI, 280 .parent = TYPE_VIRTIO_SCSI_COMMON, 281 .instance_size = sizeof(VHostSCSI), 282 .class_init = vhost_scsi_class_init, 283 }; 284 285 static void virtio_register_types(void) 286 { 287 type_register_static(&vhost_scsi_info); 288 } 289 290 type_init(virtio_register_types) 291