| 1 | /* |
| 2 | * VirtioBus |
| 3 | * |
| 4 | * Copyright (C) 2012 : GreenSocs Ltd |
| 5 | * http://www.greensocs.com/ , email: info@greensocs.com |
| 6 | * |
| 7 | * Developed by : |
| 8 | * Frederic Konrad <fred.konrad@greensocs.com> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation, either version 2 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License along |
| 21 | * with this program; if not, see <http://www.gnu.org/licenses/>. |
| 22 | * |
| 23 | */ |
| 24 | |
| 25 | #include "qemu/osdep.h" |
| 26 | #include "qemu/error-report.h" |
| 27 | #include "qemu/module.h" |
| 28 | #include "qapi/error.h" |
| 29 | #include "hw/virtio/virtio-bus.h" |
| 30 | #include "hw/virtio/virtio.h" |
| 31 | #include "system/address-spaces.h" |
| 32 | |
| 33 | /* #define DEBUG_VIRTIO_BUS */ |
| 34 | |
| 35 | #ifdef DEBUG_VIRTIO_BUS |
| 36 | #define DPRINTF(fmt, ...) \ |
| 37 | do { printf("virtio_bus: " fmt , ## __VA_ARGS__); } while (0) |
| 38 | #else |
| 39 | #define DPRINTF(fmt, ...) do { } while (0) |
| 40 | #endif |
| 41 | |
| 42 | /* A VirtIODevice is being plugged */ |
| 43 | void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp) |
| 44 | { |
| 45 | DeviceState *qdev = DEVICE(vdev); |
| 46 | BusState *qbus = BUS(qdev_get_parent_bus(qdev)); |
| 47 | VirtioBusState *bus = VIRTIO_BUS(qbus); |
| 48 | VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus); |
| 49 | VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 50 | bool has_iommu = virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); |
| 51 | bool vdev_has_iommu; |
| 52 | Error *local_err = NULL; |
| 53 | |
| 54 | DPRINTF("%s: plug device.\n", qbus->name); |
| 55 | |
| 56 | if (klass->pre_plugged != NULL) { |
| 57 | klass->pre_plugged(qbus->parent, &local_err); |
| 58 | if (local_err) { |
| 59 | error_propagate(errp, local_err); |
| 60 | return; |
| 61 | } |
| 62 | } |
| 63 | |
| 64 | /* Get the features of the plugged device. */ |
| 65 | if (vdc->get_features_ex) { |
| 66 | vdc->get_features_ex(vdev, vdev->host_features_ex, &local_err); |
| 67 | } else { |
| 68 | assert(vdc->get_features != NULL); |
| 69 | virtio_features_from_u64(vdev->host_features_ex, |
| 70 | vdc->get_features(vdev, vdev->host_features, |
| 71 | &local_err)); |
| 72 | } |
| 73 | if (local_err) { |
| 74 | error_propagate(errp, local_err); |
| 75 | return; |
| 76 | } |
| 77 | |
| 78 | if (klass->device_plugged != NULL) { |
| 79 | klass->device_plugged(qbus->parent, &local_err); |
| 80 | } |
| 81 | if (local_err) { |
| 82 | error_propagate(errp, local_err); |
| 83 | return; |
| 84 | } |
| 85 | |
| 86 | vdev->dma_as = &address_space_memory; |
| 87 | if (has_iommu) { |
| 88 | vdev_has_iommu = virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); |
| 89 | /* |
| 90 | * Present IOMMU_PLATFORM to the driver iff iommu_plattform=on and |
| 91 | * device operational. If the driver does not accept IOMMU_PLATFORM |
| 92 | * we fail the device. |
| 93 | */ |
| 94 | virtio_add_feature(&vdev->host_features, VIRTIO_F_IOMMU_PLATFORM); |
| 95 | if (klass->get_dma_as) { |
| 96 | vdev->dma_as = klass->get_dma_as(qbus->parent); |
| 97 | if (!vdev_has_iommu && vdev->dma_as != &address_space_memory) { |
| 98 | error_setg(errp, |
| 99 | "iommu_platform=true is not supported by the device"); |
| 100 | return; |
| 101 | } |
| 102 | } |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | /* Reset the virtio_bus */ |
| 107 | void virtio_bus_reset(VirtioBusState *bus) |
| 108 | { |
| 109 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 110 | |
| 111 | DPRINTF("%s: reset device.\n", BUS(bus)->name); |
| 112 | virtio_bus_stop_ioeventfd(bus); |
| 113 | if (vdev != NULL) { |
| 114 | virtio_reset(vdev); |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | /* A VirtIODevice is being unplugged */ |
| 119 | void virtio_bus_device_unplugged(VirtIODevice *vdev) |
| 120 | { |
| 121 | DeviceState *qdev = DEVICE(vdev); |
| 122 | BusState *qbus = BUS(qdev_get_parent_bus(qdev)); |
| 123 | VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(qbus); |
| 124 | |
| 125 | DPRINTF("%s: remove device.\n", qbus->name); |
| 126 | |
| 127 | if (vdev != NULL) { |
| 128 | if (klass->device_unplugged != NULL) { |
| 129 | klass->device_unplugged(qbus->parent); |
| 130 | } |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | /* Get the device id of the plugged device. */ |
| 135 | uint16_t virtio_bus_get_vdev_id(VirtioBusState *bus) |
| 136 | { |
| 137 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 138 | assert(vdev != NULL); |
| 139 | return vdev->device_id; |
| 140 | } |
| 141 | |
| 142 | /* Get the config_len field of the plugged device. */ |
| 143 | size_t virtio_bus_get_vdev_config_len(VirtioBusState *bus) |
| 144 | { |
| 145 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 146 | assert(vdev != NULL); |
| 147 | return vdev->config_len; |
| 148 | } |
| 149 | |
| 150 | /* Get bad features of the plugged device. */ |
| 151 | uint32_t virtio_bus_get_vdev_bad_features(VirtioBusState *bus) |
| 152 | { |
| 153 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 154 | VirtioDeviceClass *k; |
| 155 | |
| 156 | assert(vdev != NULL); |
| 157 | k = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 158 | if (k->bad_features != NULL) { |
| 159 | return k->bad_features(vdev); |
| 160 | } else { |
| 161 | return 0; |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | /* Get config of the plugged device. */ |
| 166 | void virtio_bus_get_vdev_config(VirtioBusState *bus, uint8_t *config) |
| 167 | { |
| 168 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 169 | VirtioDeviceClass *k; |
| 170 | |
| 171 | assert(vdev != NULL); |
| 172 | k = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 173 | if (k->get_config != NULL) { |
| 174 | k->get_config(vdev, config); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | /* Set config of the plugged device. */ |
| 179 | void virtio_bus_set_vdev_config(VirtioBusState *bus, uint8_t *config) |
| 180 | { |
| 181 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 182 | VirtioDeviceClass *k; |
| 183 | |
| 184 | assert(vdev != NULL); |
| 185 | k = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 186 | if (k->set_config != NULL) { |
| 187 | k->set_config(vdev, config); |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | /* On success, ioeventfd ownership belongs to the caller. */ |
| 192 | int virtio_bus_grab_ioeventfd(VirtioBusState *bus) |
| 193 | { |
| 194 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus); |
| 195 | |
| 196 | /* vhost can be used even if ioeventfd=off in the proxy device, |
| 197 | * so do not check k->ioeventfd_enabled. |
| 198 | */ |
| 199 | if (!k->ioeventfd_assign) { |
| 200 | return -ENOSYS; |
| 201 | } |
| 202 | |
| 203 | if (bus->ioeventfd_grabbed == 0 && bus->ioeventfd_started) { |
| 204 | virtio_bus_stop_ioeventfd(bus); |
| 205 | /* Remember that we need to restart ioeventfd |
| 206 | * when ioeventfd_grabbed becomes zero. |
| 207 | */ |
| 208 | bus->ioeventfd_started = true; |
| 209 | } |
| 210 | bus->ioeventfd_grabbed++; |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | void virtio_bus_release_ioeventfd(VirtioBusState *bus) |
| 215 | { |
| 216 | assert(bus->ioeventfd_grabbed != 0); |
| 217 | if (--bus->ioeventfd_grabbed == 0 && bus->ioeventfd_started) { |
| 218 | /* Force virtio_bus_start_ioeventfd to act. */ |
| 219 | bus->ioeventfd_started = false; |
| 220 | virtio_bus_start_ioeventfd(bus); |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | int virtio_bus_start_ioeventfd(VirtioBusState *bus) |
| 225 | { |
| 226 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus); |
| 227 | DeviceState *proxy = DEVICE(BUS(bus)->parent); |
| 228 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 229 | VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 230 | int r; |
| 231 | |
| 232 | if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) { |
| 233 | return -ENOSYS; |
| 234 | } |
| 235 | if (bus->ioeventfd_started) { |
| 236 | return 0; |
| 237 | } |
| 238 | |
| 239 | /* Only set our notifier if we have ownership. */ |
| 240 | if (!bus->ioeventfd_grabbed) { |
| 241 | r = vdc->start_ioeventfd(vdev); |
| 242 | if (r < 0) { |
| 243 | error_report("%s: failed. Fallback to userspace (slower).", __func__); |
| 244 | return r; |
| 245 | } |
| 246 | } |
| 247 | bus->ioeventfd_started = true; |
| 248 | return 0; |
| 249 | } |
| 250 | |
| 251 | void virtio_bus_stop_ioeventfd(VirtioBusState *bus) |
| 252 | { |
| 253 | VirtIODevice *vdev; |
| 254 | VirtioDeviceClass *vdc; |
| 255 | |
| 256 | if (!bus->ioeventfd_started) { |
| 257 | return; |
| 258 | } |
| 259 | |
| 260 | /* Only remove our notifier if we have ownership. */ |
| 261 | if (!bus->ioeventfd_grabbed) { |
| 262 | vdev = virtio_bus_get_device(bus); |
| 263 | vdc = VIRTIO_DEVICE_GET_CLASS(vdev); |
| 264 | vdc->stop_ioeventfd(vdev); |
| 265 | } |
| 266 | bus->ioeventfd_started = false; |
| 267 | } |
| 268 | |
| 269 | bool virtio_bus_ioeventfd_enabled(VirtioBusState *bus) |
| 270 | { |
| 271 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus); |
| 272 | DeviceState *proxy = DEVICE(BUS(bus)->parent); |
| 273 | |
| 274 | return k->ioeventfd_assign && k->ioeventfd_enabled(proxy); |
| 275 | } |
| 276 | |
| 277 | /* |
| 278 | * This function switches ioeventfd on/off in the device. |
| 279 | * The caller must set or clear the handlers for the EventNotifier. |
| 280 | */ |
| 281 | int virtio_bus_set_host_notifier(VirtioBusState *bus, int n, bool assign) |
| 282 | { |
| 283 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 284 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus); |
| 285 | DeviceState *proxy = DEVICE(BUS(bus)->parent); |
| 286 | VirtQueue *vq = virtio_get_queue(vdev, n); |
| 287 | EventNotifier *notifier = virtio_queue_get_host_notifier(vq); |
| 288 | int r = 0; |
| 289 | |
| 290 | if (!k->ioeventfd_assign) { |
| 291 | return -ENOSYS; |
| 292 | } |
| 293 | |
| 294 | if (assign) { |
| 295 | r = event_notifier_init(notifier, 1); |
| 296 | if (r < 0) { |
| 297 | error_report("%s: unable to init event notifier: %s (%d)", |
| 298 | __func__, strerror(-r), r); |
| 299 | return r; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | r = k->ioeventfd_assign(proxy, notifier, n, assign); |
| 304 | if (r < 0 && assign) { |
| 305 | error_report("%s: unable to assign ioeventfd: %d", __func__, r); |
| 306 | virtio_bus_cleanup_host_notifier(bus, n); |
| 307 | return r; |
| 308 | } |
| 309 | |
| 310 | virtio_queue_set_host_notifier_enabled(vq, assign); |
| 311 | |
| 312 | return 0; |
| 313 | } |
| 314 | |
| 315 | void virtio_bus_cleanup_host_notifier(VirtioBusState *bus, int n) |
| 316 | { |
| 317 | VirtIODevice *vdev = virtio_bus_get_device(bus); |
| 318 | VirtQueue *vq = virtio_get_queue(vdev, n); |
| 319 | EventNotifier *notifier = virtio_queue_get_host_notifier(vq); |
| 320 | |
| 321 | /* Test and clear notifier after disabling event, |
| 322 | * in case poll callback didn't have time to run. |
| 323 | */ |
| 324 | virtio_queue_host_notifier_read(notifier); |
| 325 | event_notifier_cleanup(notifier); |
| 326 | } |
| 327 | |
| 328 | static char *virtio_bus_get_dev_path(DeviceState *dev) |
| 329 | { |
| 330 | BusState *bus = qdev_get_parent_bus(dev); |
| 331 | DeviceState *proxy = DEVICE(bus->parent); |
| 332 | return qdev_get_dev_path(proxy); |
| 333 | } |
| 334 | |
| 335 | static char *virtio_bus_get_fw_dev_path(DeviceState *dev) |
| 336 | { |
| 337 | return NULL; |
| 338 | } |
| 339 | |
| 340 | bool virtio_bus_device_iommu_enabled(VirtIODevice *vdev) |
| 341 | { |
| 342 | DeviceState *qdev = DEVICE(vdev); |
| 343 | BusState *qbus = BUS(qdev_get_parent_bus(qdev)); |
| 344 | VirtioBusState *bus = VIRTIO_BUS(qbus); |
| 345 | VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus); |
| 346 | |
| 347 | if (!klass->iommu_enabled) { |
| 348 | return false; |
| 349 | } |
| 350 | |
| 351 | return klass->iommu_enabled(qbus->parent); |
| 352 | } |
| 353 | |
| 354 | static void virtio_bus_class_init(ObjectClass *klass, const void *data) |
| 355 | { |
| 356 | BusClass *bus_class = BUS_CLASS(klass); |
| 357 | bus_class->get_dev_path = virtio_bus_get_dev_path; |
| 358 | bus_class->get_fw_dev_path = virtio_bus_get_fw_dev_path; |
| 359 | } |
| 360 | |
| 361 | static const TypeInfo virtio_bus_info = { |
| 362 | .name = TYPE_VIRTIO_BUS, |
| 363 | .parent = TYPE_BUS, |
| 364 | .instance_size = sizeof(VirtioBusState), |
| 365 | .abstract = true, |
| 366 | .class_size = sizeof(VirtioBusClass), |
| 367 | .class_init = virtio_bus_class_init |
| 368 | }; |
| 369 | |
| 370 | static void virtio_register_types(void) |
| 371 | { |
| 372 | type_register_static(&virtio_bus_info); |
| 373 | } |
| 374 | |
| 375 | type_init(virtio_register_types) |