hw/virtio/virtio-mmio.c

   1 /*
   2  * Virtio MMIO bindings
   3  *
   4  * Copyright (c) 2011 Linaro Limited
   5  *
   6  * Author:
   7  *  Peter Maydell <peter.maydell@linaro.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License; either version 2
  11  * of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "qemu/osdep.h"
  23 #include "standard-headers/linux/virtio_mmio.h"
  24 #include "hw/irq.h"
  25 #include "hw/qdev-properties.h"
  26 #include "hw/sysbus.h"
  27 #include "hw/virtio/virtio.h"
  28 #include "migration/qemu-file-types.h"
  29 #include "qemu/host-utils.h"
  30 #include "qemu/module.h"
  31 #include "sysemu/kvm.h"
  32 #include "hw/virtio/virtio-mmio.h"
  33 #include "qemu/error-report.h"
  34 #include "qemu/log.h"
  35 #include "trace.h"
  36
  37 static bool virtio_mmio_ioeventfd_enabled(DeviceState *d)
  38 {
  39     return kvm_eventfds_enabled();
  40 }
  41
  42 static int virtio_mmio_ioeventfd_assign(DeviceState *d,
  43                                         EventNotifier *notifier,
  44                                         int n, bool assign)
  45 {
  46     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
  47
  48     if (assign) {
  49         memory_region_add_eventfd(&proxy->iomem, VIRTIO_MMIO_QUEUE_NOTIFY, 4,
  50                                   true, n, notifier);
  51     } else {
  52         memory_region_del_eventfd(&proxy->iomem, VIRTIO_MMIO_QUEUE_NOTIFY, 4,
  53                                   true, n, notifier);
  54     }
  55     return 0;
  56 }
  57
  58 static void virtio_mmio_start_ioeventfd(VirtIOMMIOProxy *proxy)
  59 {
  60     virtio_bus_start_ioeventfd(&proxy->bus);
  61 }
  62
  63 static void virtio_mmio_stop_ioeventfd(VirtIOMMIOProxy *proxy)
  64 {
  65     virtio_bus_stop_ioeventfd(&proxy->bus);
  66 }
  67
  68 static void virtio_mmio_soft_reset(VirtIOMMIOProxy *proxy)
  69 {
  70     int i;
  71
  72     if (proxy->legacy) {
  73         return;
  74     }
  75
  76     for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
  77         proxy->vqs[i].enabled = 0;
  78     }
  79 }
  80
  81 static uint64_t virtio_mmio_read(void *opaque, hwaddr offset, unsigned size)
  82 {
  83     VirtIOMMIOProxy *proxy = (VirtIOMMIOProxy *)opaque;
  84     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
  85
  86     trace_virtio_mmio_read(offset);
  87
  88     if (!vdev) {
  89         /* If no backend is present, we treat most registers as
  90          * read-as-zero, except for the magic number, version and
  91          * vendor ID. This is not strictly sanctioned by the virtio
  92          * spec, but it allows us to provide transports with no backend
  93          * plugged in which don't confuse Linux's virtio code: the
  94          * probe won't complain about the bad magic number, but the
  95          * device ID of zero means no backend will claim it.
  96          */
  97         switch (offset) {
  98         case VIRTIO_MMIO_MAGIC_VALUE:
  99             return VIRT_MAGIC;
 100         case VIRTIO_MMIO_VERSION:
 101             if (proxy->legacy) {
 102                 return VIRT_VERSION_LEGACY;
 103             } else {
 104                 return VIRT_VERSION;
 105             }
 106         case VIRTIO_MMIO_VENDOR_ID:
 107             return VIRT_VENDOR;
 108         default:
 109             return 0;
 110         }
 111     }
 112
 113     if (offset >= VIRTIO_MMIO_CONFIG) {
 114         offset -= VIRTIO_MMIO_CONFIG;
 115         switch (size) {
 116         case 1:
 117             return virtio_config_readb(vdev, offset);
 118         case 2:
 119             return virtio_config_readw(vdev, offset);
 120         case 4:
 121             return virtio_config_readl(vdev, offset);
 122         default:
 123             abort();
 124         }
 125     }
 126     if (size != 4) {
 127         qemu_log_mask(LOG_GUEST_ERROR,
 128                       "%s: wrong size access to register!\n",
 129                       __func__);
 130         return 0;
 131     }
 132     switch (offset) {
 133     case VIRTIO_MMIO_MAGIC_VALUE:
 134         return VIRT_MAGIC;
 135     case VIRTIO_MMIO_VERSION:
 136         if (proxy->legacy) {
 137             return VIRT_VERSION_LEGACY;
 138         } else {
 139             return VIRT_VERSION;
 140         }
 141     case VIRTIO_MMIO_DEVICE_ID:
 142         return vdev->device_id;
 143     case VIRTIO_MMIO_VENDOR_ID:
 144         return VIRT_VENDOR;
 145     case VIRTIO_MMIO_DEVICE_FEATURES:
 146         if (proxy->legacy) {
 147             if (proxy->host_features_sel) {
 148                 return 0;
 149             } else {
 150                 return vdev->host_features;
 151             }
 152         } else {
 153             VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
 154             return (vdev->host_features & ~vdc->legacy_features)
 155                 >> (32 * proxy->host_features_sel);
 156         }
 157     case VIRTIO_MMIO_QUEUE_NUM_MAX:
 158         if (!virtio_queue_get_num(vdev, vdev->queue_sel)) {
 159             return 0;
 160         }
 161         return VIRTQUEUE_MAX_SIZE;
 162     case VIRTIO_MMIO_QUEUE_PFN:
 163         if (!proxy->legacy) {
 164             qemu_log_mask(LOG_GUEST_ERROR,
 165                           "%s: read from legacy register (0x%"
 166                           HWADDR_PRIx ") in non-legacy mode\n",
 167                           __func__, offset);
 168             return 0;
 169         }
 170         return virtio_queue_get_addr(vdev, vdev->queue_sel)
 171             >> proxy->guest_page_shift;
 172     case VIRTIO_MMIO_QUEUE_READY:
 173         if (proxy->legacy) {
 174             qemu_log_mask(LOG_GUEST_ERROR,
 175                           "%s: read from non-legacy register (0x%"
 176                           HWADDR_PRIx ") in legacy mode\n",
 177                           __func__, offset);
 178             return 0;
 179         }
 180         return proxy->vqs[vdev->queue_sel].enabled;
 181     case VIRTIO_MMIO_INTERRUPT_STATUS:
 182         return qatomic_read(&vdev->isr);
 183     case VIRTIO_MMIO_STATUS:
 184         return vdev->status;
 185     case VIRTIO_MMIO_CONFIG_GENERATION:
 186         if (proxy->legacy) {
 187             qemu_log_mask(LOG_GUEST_ERROR,
 188                           "%s: read from non-legacy register (0x%"
 189                           HWADDR_PRIx ") in legacy mode\n",
 190                           __func__, offset);
 191             return 0;
 192         }
 193         return vdev->generation;
 194    case VIRTIO_MMIO_SHM_LEN_LOW:
 195    case VIRTIO_MMIO_SHM_LEN_HIGH:
 196         /*
 197          * VIRTIO_MMIO_SHM_SEL is unimplemented
 198          * according to the linux driver, if region length is -1
 199          * the shared memory doesn't exist
 200          */
 201         return -1;
 202     case VIRTIO_MMIO_DEVICE_FEATURES_SEL:
 203     case VIRTIO_MMIO_DRIVER_FEATURES:
 204     case VIRTIO_MMIO_DRIVER_FEATURES_SEL:
 205     case VIRTIO_MMIO_GUEST_PAGE_SIZE:
 206     case VIRTIO_MMIO_QUEUE_SEL:
 207     case VIRTIO_MMIO_QUEUE_NUM:
 208     case VIRTIO_MMIO_QUEUE_ALIGN:
 209     case VIRTIO_MMIO_QUEUE_NOTIFY:
 210     case VIRTIO_MMIO_INTERRUPT_ACK:
 211     case VIRTIO_MMIO_QUEUE_DESC_LOW:
 212     case VIRTIO_MMIO_QUEUE_DESC_HIGH:
 213     case VIRTIO_MMIO_QUEUE_AVAIL_LOW:
 214     case VIRTIO_MMIO_QUEUE_AVAIL_HIGH:
 215     case VIRTIO_MMIO_QUEUE_USED_LOW:
 216     case VIRTIO_MMIO_QUEUE_USED_HIGH:
 217         qemu_log_mask(LOG_GUEST_ERROR,
 218                       "%s: read of write-only register (0x%" HWADDR_PRIx ")\n",
 219                       __func__, offset);
 220         return 0;
 221     default:
 222         qemu_log_mask(LOG_GUEST_ERROR,
 223                       "%s: bad register offset (0x%" HWADDR_PRIx ")\n",
 224                       __func__, offset);
 225         return 0;
 226     }
 227     return 0;
 228 }
 229
 230 static void virtio_mmio_write(void *opaque, hwaddr offset, uint64_t value,
 231                               unsigned size)
 232 {
 233     VirtIOMMIOProxy *proxy = (VirtIOMMIOProxy *)opaque;
 234     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
 235
 236     trace_virtio_mmio_write_offset(offset, value);
 237
 238     if (!vdev) {
 239         /* If no backend is present, we just make all registers
 240          * write-ignored. This allows us to provide transports with
 241          * no backend plugged in.
 242          */
 243         return;
 244     }
 245
 246     if (offset >= VIRTIO_MMIO_CONFIG) {
 247         offset -= VIRTIO_MMIO_CONFIG;
 248         switch (size) {
 249         case 1:
 250             virtio_config_writeb(vdev, offset, value);
 251             break;
 252         case 2:
 253             virtio_config_writew(vdev, offset, value);
 254             break;
 255         case 4:
 256             virtio_config_writel(vdev, offset, value);
 257             break;
 258         default:
 259             abort();
 260         }
 261         return;
 262     }
 263     if (size != 4) {
 264         qemu_log_mask(LOG_GUEST_ERROR,
 265                       "%s: wrong size access to register!\n",
 266                       __func__);
 267         return;
 268     }
 269     switch (offset) {
 270     case VIRTIO_MMIO_DEVICE_FEATURES_SEL:
 271         if (value) {
 272             proxy->host_features_sel = 1;
 273         } else {
 274             proxy->host_features_sel = 0;
 275         }
 276         break;
 277     case VIRTIO_MMIO_DRIVER_FEATURES:
 278         if (proxy->legacy) {
 279             if (proxy->guest_features_sel) {
 280                 qemu_log_mask(LOG_GUEST_ERROR,
 281                               "%s: attempt to write guest features with "
 282                               "guest_features_sel > 0 in legacy mode\n",
 283                               __func__);
 284             } else {
 285                 virtio_set_features(vdev, value);
 286             }
 287         } else {
 288             proxy->guest_features[proxy->guest_features_sel] = value;
 289         }
 290         break;
 291     case VIRTIO_MMIO_DRIVER_FEATURES_SEL:
 292         if (value) {
 293             proxy->guest_features_sel = 1;
 294         } else {
 295             proxy->guest_features_sel = 0;
 296         }
 297         break;
 298     case VIRTIO_MMIO_GUEST_PAGE_SIZE:
 299         if (!proxy->legacy) {
 300             qemu_log_mask(LOG_GUEST_ERROR,
 301                           "%s: write to legacy register (0x%"
 302                           HWADDR_PRIx ") in non-legacy mode\n",
 303                           __func__, offset);
 304             return;
 305         }
 306         proxy->guest_page_shift = ctz32(value);
 307         if (proxy->guest_page_shift > 31) {
 308             proxy->guest_page_shift = 0;
 309         }
 310         trace_virtio_mmio_guest_page(value, proxy->guest_page_shift);
 311         break;
 312     case VIRTIO_MMIO_QUEUE_SEL:
 313         if (value < VIRTIO_QUEUE_MAX) {
 314             vdev->queue_sel = value;
 315         }
 316         break;
 317     case VIRTIO_MMIO_QUEUE_NUM:
 318         trace_virtio_mmio_queue_write(value, VIRTQUEUE_MAX_SIZE);
 319         virtio_queue_set_num(vdev, vdev->queue_sel, value);
 320
 321         if (proxy->legacy) {
 322             virtio_queue_update_rings(vdev, vdev->queue_sel);
 323         } else {
 324             proxy->vqs[vdev->queue_sel].num = value;
 325         }
 326         break;
 327     case VIRTIO_MMIO_QUEUE_ALIGN:
 328         if (!proxy->legacy) {
 329             qemu_log_mask(LOG_GUEST_ERROR,
 330                           "%s: write to legacy register (0x%"
 331                           HWADDR_PRIx ") in non-legacy mode\n",
 332                           __func__, offset);
 333             return;
 334         }
 335         virtio_queue_set_align(vdev, vdev->queue_sel, value);
 336         break;
 337     case VIRTIO_MMIO_QUEUE_PFN:
 338         if (!proxy->legacy) {
 339             qemu_log_mask(LOG_GUEST_ERROR,
 340                           "%s: write to legacy register (0x%"
 341                           HWADDR_PRIx ") in non-legacy mode\n",
 342                           __func__, offset);
 343             return;
 344         }
 345         if (value == 0) {
 346             virtio_reset(vdev);
 347         } else {
 348             virtio_queue_set_addr(vdev, vdev->queue_sel,
 349                                   value << proxy->guest_page_shift);
 350         }
 351         break;
 352     case VIRTIO_MMIO_QUEUE_READY:
 353         if (proxy->legacy) {
 354             qemu_log_mask(LOG_GUEST_ERROR,
 355                           "%s: write to non-legacy register (0x%"
 356                           HWADDR_PRIx ") in legacy mode\n",
 357                           __func__, offset);
 358             return;
 359         }
 360         if (value) {
 361             virtio_queue_set_num(vdev, vdev->queue_sel,
 362                                  proxy->vqs[vdev->queue_sel].num);
 363             virtio_queue_set_rings(vdev, vdev->queue_sel,
 364                 ((uint64_t)proxy->vqs[vdev->queue_sel].desc[1]) << 32 |
 365                 proxy->vqs[vdev->queue_sel].desc[0],
 366                 ((uint64_t)proxy->vqs[vdev->queue_sel].avail[1]) << 32 |
 367                 proxy->vqs[vdev->queue_sel].avail[0],
 368                 ((uint64_t)proxy->vqs[vdev->queue_sel].used[1]) << 32 |
 369                 proxy->vqs[vdev->queue_sel].used[0]);
 370             proxy->vqs[vdev->queue_sel].enabled = 1;
 371         } else {
 372             proxy->vqs[vdev->queue_sel].enabled = 0;
 373         }
 374         break;
 375     case VIRTIO_MMIO_QUEUE_NOTIFY:
 376         if (value < VIRTIO_QUEUE_MAX) {
 377             virtio_queue_notify(vdev, value);
 378         }
 379         break;
 380     case VIRTIO_MMIO_INTERRUPT_ACK:
 381         qatomic_and(&vdev->isr, ~value);
 382         virtio_update_irq(vdev);
 383         break;
 384     case VIRTIO_MMIO_STATUS:
 385         if (!(value & VIRTIO_CONFIG_S_DRIVER_OK)) {
 386             virtio_mmio_stop_ioeventfd(proxy);
 387         }
 388
 389         if (!proxy->legacy && (value & VIRTIO_CONFIG_S_FEATURES_OK)) {
 390             virtio_set_features(vdev,
 391                                 ((uint64_t)proxy->guest_features[1]) << 32 |
 392                                 proxy->guest_features[0]);
 393         }
 394
 395         virtio_set_status(vdev, value & 0xff);
 396
 397         if (value & VIRTIO_CONFIG_S_DRIVER_OK) {
 398             virtio_mmio_start_ioeventfd(proxy);
 399         }
 400
 401         if (vdev->status == 0) {
 402             virtio_reset(vdev);
 403             virtio_mmio_soft_reset(proxy);
 404         }
 405         break;
 406     case VIRTIO_MMIO_QUEUE_DESC_LOW:
 407         if (proxy->legacy) {
 408             qemu_log_mask(LOG_GUEST_ERROR,
 409                           "%s: write to non-legacy register (0x%"
 410                           HWADDR_PRIx ") in legacy mode\n",
 411                           __func__, offset);
 412             return;
 413         }
 414         proxy->vqs[vdev->queue_sel].desc[0] = value;
 415         break;
 416     case VIRTIO_MMIO_QUEUE_DESC_HIGH:
 417         if (proxy->legacy) {
 418             qemu_log_mask(LOG_GUEST_ERROR,
 419                           "%s: write to non-legacy register (0x%"
 420                           HWADDR_PRIx ") in legacy mode\n",
 421                           __func__, offset);
 422             return;
 423         }
 424         proxy->vqs[vdev->queue_sel].desc[1] = value;
 425         break;
 426     case VIRTIO_MMIO_QUEUE_AVAIL_LOW:
 427         if (proxy->legacy) {
 428             qemu_log_mask(LOG_GUEST_ERROR,
 429                           "%s: write to non-legacy register (0x%"
 430                           HWADDR_PRIx ") in legacy mode\n",
 431                           __func__, offset);
 432             return;
 433         }
 434         proxy->vqs[vdev->queue_sel].avail[0] = value;
 435         break;
 436     case VIRTIO_MMIO_QUEUE_AVAIL_HIGH:
 437         if (proxy->legacy) {
 438             qemu_log_mask(LOG_GUEST_ERROR,
 439                           "%s: write to non-legacy register (0x%"
 440                           HWADDR_PRIx ") in legacy mode\n",
 441                           __func__, offset);
 442             return;
 443         }
 444         proxy->vqs[vdev->queue_sel].avail[1] = value;
 445         break;
 446     case VIRTIO_MMIO_QUEUE_USED_LOW:
 447         if (proxy->legacy) {
 448             qemu_log_mask(LOG_GUEST_ERROR,
 449                           "%s: write to non-legacy register (0x%"
 450                           HWADDR_PRIx ") in legacy mode\n",
 451                           __func__, offset);
 452             return;
 453         }
 454         proxy->vqs[vdev->queue_sel].used[0] = value;
 455         break;
 456     case VIRTIO_MMIO_QUEUE_USED_HIGH:
 457         if (proxy->legacy) {
 458             qemu_log_mask(LOG_GUEST_ERROR,
 459                           "%s: write to non-legacy register (0x%"
 460                           HWADDR_PRIx ") in legacy mode\n",
 461                           __func__, offset);
 462             return;
 463         }
 464         proxy->vqs[vdev->queue_sel].used[1] = value;
 465         break;
 466     case VIRTIO_MMIO_MAGIC_VALUE:
 467     case VIRTIO_MMIO_VERSION:
 468     case VIRTIO_MMIO_DEVICE_ID:
 469     case VIRTIO_MMIO_VENDOR_ID:
 470     case VIRTIO_MMIO_DEVICE_FEATURES:
 471     case VIRTIO_MMIO_QUEUE_NUM_MAX:
 472     case VIRTIO_MMIO_INTERRUPT_STATUS:
 473     case VIRTIO_MMIO_CONFIG_GENERATION:
 474         qemu_log_mask(LOG_GUEST_ERROR,
 475                       "%s: write to read-only register (0x%" HWADDR_PRIx ")\n",
 476                       __func__, offset);
 477         break;
 478
 479     default:
 480         qemu_log_mask(LOG_GUEST_ERROR,
 481                       "%s: bad register offset (0x%" HWADDR_PRIx ")\n",
 482                       __func__, offset);
 483     }
 484 }
 485
 486 static const MemoryRegionOps virtio_legacy_mem_ops = {
 487     .read = virtio_mmio_read,
 488     .write = virtio_mmio_write,
 489     .endianness = DEVICE_NATIVE_ENDIAN,
 490 };
 491
 492 static const MemoryRegionOps virtio_mem_ops = {
 493     .read = virtio_mmio_read,
 494     .write = virtio_mmio_write,
 495     .endianness = DEVICE_LITTLE_ENDIAN,
 496 };
 497
 498 static void virtio_mmio_update_irq(DeviceState *opaque, uint16_t vector)
 499 {
 500     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 501     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
 502     int level;
 503
 504     if (!vdev) {
 505         return;
 506     }
 507     level = (qatomic_read(&vdev->isr) != 0);
 508     trace_virtio_mmio_setting_irq(level);
 509     qemu_set_irq(proxy->irq, level);
 510 }
 511
 512 static int virtio_mmio_load_config(DeviceState *opaque, QEMUFile *f)
 513 {
 514     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 515
 516     proxy->host_features_sel = qemu_get_be32(f);
 517     proxy->guest_features_sel = qemu_get_be32(f);
 518     proxy->guest_page_shift = qemu_get_be32(f);
 519     return 0;
 520 }
 521
 522 static void virtio_mmio_save_config(DeviceState *opaque, QEMUFile *f)
 523 {
 524     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 525
 526     qemu_put_be32(f, proxy->host_features_sel);
 527     qemu_put_be32(f, proxy->guest_features_sel);
 528     qemu_put_be32(f, proxy->guest_page_shift);
 529 }
 530
 531 static const VMStateDescription vmstate_virtio_mmio_queue_state = {
 532     .name = "virtio_mmio/queue_state",
 533     .version_id = 1,
 534     .minimum_version_id = 1,
 535     .fields = (VMStateField[]) {
 536         VMSTATE_UINT16(num, VirtIOMMIOQueue),
 537         VMSTATE_BOOL(enabled, VirtIOMMIOQueue),
 538         VMSTATE_UINT32_ARRAY(desc, VirtIOMMIOQueue, 2),
 539         VMSTATE_UINT32_ARRAY(avail, VirtIOMMIOQueue, 2),
 540         VMSTATE_UINT32_ARRAY(used, VirtIOMMIOQueue, 2),
 541         VMSTATE_END_OF_LIST()
 542     }
 543 };
 544
 545 static const VMStateDescription vmstate_virtio_mmio_state_sub = {
 546     .name = "virtio_mmio/state",
 547     .version_id = 1,
 548     .minimum_version_id = 1,
 549     .fields = (VMStateField[]) {
 550         VMSTATE_UINT32_ARRAY(guest_features, VirtIOMMIOProxy, 2),
 551         VMSTATE_STRUCT_ARRAY(vqs, VirtIOMMIOProxy, VIRTIO_QUEUE_MAX, 0,
 552                              vmstate_virtio_mmio_queue_state,
 553                              VirtIOMMIOQueue),
 554         VMSTATE_END_OF_LIST()
 555     }
 556 };
 557
 558 static const VMStateDescription vmstate_virtio_mmio = {
 559     .name = "virtio_mmio",
 560     .version_id = 1,
 561     .minimum_version_id = 1,
 562     .minimum_version_id_old = 1,
 563     .fields = (VMStateField[]) {
 564         VMSTATE_END_OF_LIST()
 565     },
 566     .subsections = (const VMStateDescription * []) {
 567         &vmstate_virtio_mmio_state_sub,
 568         NULL
 569     }
 570 };
 571
 572 static void virtio_mmio_save_extra_state(DeviceState *opaque, QEMUFile *f)
 573 {
 574     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 575
 576     vmstate_save_state(f, &vmstate_virtio_mmio, proxy, NULL);
 577 }
 578
 579 static int virtio_mmio_load_extra_state(DeviceState *opaque, QEMUFile *f)
 580 {
 581     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 582
 583     return vmstate_load_state(f, &vmstate_virtio_mmio, proxy, 1);
 584 }
 585
 586 static bool virtio_mmio_has_extra_state(DeviceState *opaque)
 587 {
 588     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque);
 589
 590     return !proxy->legacy;
 591 }
 592
 593 static void virtio_mmio_reset(DeviceState *d)
 594 {
 595     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
 596     int i;
 597
 598     virtio_mmio_stop_ioeventfd(proxy);
 599     virtio_bus_reset(&proxy->bus);
 600     proxy->host_features_sel = 0;
 601     proxy->guest_features_sel = 0;
 602     proxy->guest_page_shift = 0;
 603
 604     if (!proxy->legacy) {
 605         proxy->guest_features[0] = proxy->guest_features[1] = 0;
 606
 607         for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
 608             proxy->vqs[i].enabled = 0;
 609             proxy->vqs[i].num = 0;
 610             proxy->vqs[i].desc[0] = proxy->vqs[i].desc[1] = 0;
 611             proxy->vqs[i].avail[0] = proxy->vqs[i].avail[1] = 0;
 612             proxy->vqs[i].used[0] = proxy->vqs[i].used[1] = 0;
 613         }
 614     }
 615 }
 616
 617 static int virtio_mmio_set_guest_notifier(DeviceState *d, int n, bool assign,
 618                                           bool with_irqfd)
 619 {
 620     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
 621     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
 622     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
 623     VirtQueue *vq = virtio_get_queue(vdev, n);
 624     EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
 625
 626     if (assign) {
 627         int r = event_notifier_init(notifier, 0);
 628         if (r < 0) {
 629             return r;
 630         }
 631         virtio_queue_set_guest_notifier_fd_handler(vq, true, with_irqfd);
 632     } else {
 633         virtio_queue_set_guest_notifier_fd_handler(vq, false, with_irqfd);
 634         event_notifier_cleanup(notifier);
 635     }
 636
 637     if (vdc->guest_notifier_mask && vdev->use_guest_notifier_mask) {
 638         vdc->guest_notifier_mask(vdev, n, !assign);
 639     }
 640
 641     return 0;
 642 }
 643
 644 static int virtio_mmio_set_guest_notifiers(DeviceState *d, int nvqs,
 645                                            bool assign)
 646 {
 647     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
 648     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
 649     /* TODO: need to check if kvm-arm supports irqfd */
 650     bool with_irqfd = false;
 651     int r, n;
 652
 653     nvqs = MIN(nvqs, VIRTIO_QUEUE_MAX);
 654
 655     for (n = 0; n < nvqs; n++) {
 656         if (!virtio_queue_get_num(vdev, n)) {
 657             break;
 658         }
 659
 660         r = virtio_mmio_set_guest_notifier(d, n, assign, with_irqfd);
 661         if (r < 0) {
 662             goto assign_error;
 663         }
 664     }
 665
 666     return 0;
 667
 668 assign_error:
 669     /* We get here on assignment failure. Recover by undoing for VQs 0 .. n. */
 670     assert(assign);
 671     while (--n >= 0) {
 672         virtio_mmio_set_guest_notifier(d, n, !assign, false);
 673     }
 674     return r;
 675 }
 676
 677 static void virtio_mmio_pre_plugged(DeviceState *d, Error **errp)
 678 {
 679     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
 680     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
 681
 682     if (!proxy->legacy) {
 683         virtio_add_feature(&vdev->host_features, VIRTIO_F_VERSION_1);
 684     }
 685 }
 686
 687 /* virtio-mmio device */
 688
 689 static Property virtio_mmio_properties[] = {
 690     DEFINE_PROP_BOOL("format_transport_address", VirtIOMMIOProxy,
 691                      format_transport_address, true),
 692     DEFINE_PROP_BOOL("force-legacy", VirtIOMMIOProxy, legacy, true),
 693     DEFINE_PROP_END_OF_LIST(),
 694 };
 695
 696 static void virtio_mmio_realizefn(DeviceState *d, Error **errp)
 697 {
 698     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
 699     SysBusDevice *sbd = SYS_BUS_DEVICE(d);
 700
 701     qbus_create_inplace(&proxy->bus, sizeof(proxy->bus), TYPE_VIRTIO_MMIO_BUS,
 702                         d, NULL);
 703     sysbus_init_irq(sbd, &proxy->irq);
 704     if (proxy->legacy) {
 705         memory_region_init_io(&proxy->iomem, OBJECT(d),
 706                               &virtio_legacy_mem_ops, proxy,
 707                               TYPE_VIRTIO_MMIO, 0x200);
 708     } else {
 709         memory_region_init_io(&proxy->iomem, OBJECT(d),
 710                               &virtio_mem_ops, proxy,
 711                               TYPE_VIRTIO_MMIO, 0x200);
 712     }
 713     sysbus_init_mmio(sbd, &proxy->iomem);
 714 }
 715
 716 static void virtio_mmio_class_init(ObjectClass *klass, void *data)
 717 {
 718     DeviceClass *dc = DEVICE_CLASS(klass);
 719
 720     dc->realize = virtio_mmio_realizefn;
 721     dc->reset = virtio_mmio_reset;
 722     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 723     device_class_set_props(dc, virtio_mmio_properties);
 724 }
 725
 726 static const TypeInfo virtio_mmio_info = {
 727     .name          = TYPE_VIRTIO_MMIO,
 728     .parent        = TYPE_SYS_BUS_DEVICE,
 729     .instance_size = sizeof(VirtIOMMIOProxy),
 730     .class_init    = virtio_mmio_class_init,
 731 };
 732
 733 /* virtio-mmio-bus. */
 734
 735 static char *virtio_mmio_bus_get_dev_path(DeviceState *dev)
 736 {
 737     BusState *virtio_mmio_bus;
 738     VirtIOMMIOProxy *virtio_mmio_proxy;
 739     char *proxy_path;
 740     char *path;
 741     MemoryRegionSection section;
 742
 743     virtio_mmio_bus = qdev_get_parent_bus(dev);
 744     virtio_mmio_proxy = VIRTIO_MMIO(virtio_mmio_bus->parent);
 745     proxy_path = qdev_get_dev_path(DEVICE(virtio_mmio_proxy));
 746
 747     /*
 748      * If @format_transport_address is false, then we just perform the same as
 749      * virtio_bus_get_dev_path(): we delegate the address formatting for the
 750      * device on the virtio-mmio bus to the bus that the virtio-mmio proxy
 751      * (i.e., the device that implements the virtio-mmio bus) resides on. In
 752      * this case the base address of the virtio-mmio transport will be
 753      * invisible.
 754      */
 755     if (!virtio_mmio_proxy->format_transport_address) {
 756         return proxy_path;
 757     }
 758
 759     /* Otherwise, we append the base address of the transport. */
 760     section = memory_region_find(&virtio_mmio_proxy->iomem, 0, 0x200);
 761     assert(section.mr);
 762
 763     if (proxy_path) {
 764         path = g_strdup_printf("%s/virtio-mmio@" TARGET_FMT_plx, proxy_path,
 765                                section.offset_within_address_space);
 766     } else {
 767         path = g_strdup_printf("virtio-mmio@" TARGET_FMT_plx,
 768                                section.offset_within_address_space);
 769     }
 770     memory_region_unref(section.mr);
 771
 772     g_free(proxy_path);
 773     return path;
 774 }
 775
 776 static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data)
 777 {
 778     BusClass *bus_class = BUS_CLASS(klass);
 779     VirtioBusClass *k = VIRTIO_BUS_CLASS(klass);
 780
 781     k->notify = virtio_mmio_update_irq;
 782     k->save_config = virtio_mmio_save_config;
 783     k->load_config = virtio_mmio_load_config;
 784     k->save_extra_state = virtio_mmio_save_extra_state;
 785     k->load_extra_state = virtio_mmio_load_extra_state;
 786     k->has_extra_state = virtio_mmio_has_extra_state;
 787     k->set_guest_notifiers = virtio_mmio_set_guest_notifiers;
 788     k->ioeventfd_enabled = virtio_mmio_ioeventfd_enabled;
 789     k->ioeventfd_assign = virtio_mmio_ioeventfd_assign;
 790     k->pre_plugged = virtio_mmio_pre_plugged;
 791     k->has_variable_vring_alignment = true;
 792     bus_class->max_dev = 1;
 793     bus_class->get_dev_path = virtio_mmio_bus_get_dev_path;
 794 }
 795
 796 static const TypeInfo virtio_mmio_bus_info = {
 797     .name          = TYPE_VIRTIO_MMIO_BUS,
 798     .parent        = TYPE_VIRTIO_BUS,
 799     .instance_size = sizeof(VirtioBusState),
 800     .class_init    = virtio_mmio_bus_class_init,
 801 };
 802
 803 static void virtio_mmio_register_types(void)
 804 {
 805     type_register_static(&virtio_mmio_bus_info);
 806     type_register_static(&virtio_mmio_info);
 807 }
 808
 809 type_init(virtio_mmio_register_types)