hw/vfio/helpers.c

   1 /*
   2  * low level and IOMMU backend agnostic helpers used by VFIO devices,
   3  * related to regions, interrupts, capabilities
   4  *
   5  * Copyright Red Hat, Inc. 2012
   6  *
   7  * Authors:
   8  *  Alex Williamson <alex.williamson@redhat.com>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2.  See
  11  * the COPYING file in the top-level directory.
  12  *
  13  * Based on qemu-kvm device-assignment:
  14  *  Adapted for KVM by Qumranet.
  15  *  Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com)
  16  *  Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com)
  17  *  Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com)
  18  *  Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com)
  19  *  Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com)
  20  */
  21
  22 #include "qemu/osdep.h"
  23 #include <sys/ioctl.h>
  24
  25 #include "hw/vfio/vfio-common.h"
  26 #include "hw/hw.h"
  27 #include "trace.h"
  28 #include "qapi/error.h"
  29 #include "qemu/error-report.h"
  30 #include "monitor/monitor.h"
  31
  32 /*
  33  * Common VFIO interrupt disable
  34  */
  35 void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
  36 {
  37     struct vfio_irq_set irq_set = {
  38         .argsz = sizeof(irq_set),
  39         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
  40         .index = index,
  41         .start = 0,
  42         .count = 0,
  43     };
  44
  45     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
  46 }
  47
  48 void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index)
  49 {
  50     struct vfio_irq_set irq_set = {
  51         .argsz = sizeof(irq_set),
  52         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
  53         .index = index,
  54         .start = 0,
  55         .count = 1,
  56     };
  57
  58     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
  59 }
  60
  61 void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index)
  62 {
  63     struct vfio_irq_set irq_set = {
  64         .argsz = sizeof(irq_set),
  65         .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
  66         .index = index,
  67         .start = 0,
  68         .count = 1,
  69     };
  70
  71     ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
  72 }
  73
  74 static inline const char *action_to_str(int action)
  75 {
  76     switch (action) {
  77     case VFIO_IRQ_SET_ACTION_MASK:
  78         return "MASK";
  79     case VFIO_IRQ_SET_ACTION_UNMASK:
  80         return "UNMASK";
  81     case VFIO_IRQ_SET_ACTION_TRIGGER:
  82         return "TRIGGER";
  83     default:
  84         return "UNKNOWN ACTION";
  85     }
  86 }
  87
  88 static const char *index_to_str(VFIODevice *vbasedev, int index)
  89 {
  90     if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
  91         return NULL;
  92     }
  93
  94     switch (index) {
  95     case VFIO_PCI_INTX_IRQ_INDEX:
  96         return "INTX";
  97     case VFIO_PCI_MSI_IRQ_INDEX:
  98         return "MSI";
  99     case VFIO_PCI_MSIX_IRQ_INDEX:
 100         return "MSIX";
 101     case VFIO_PCI_ERR_IRQ_INDEX:
 102         return "ERR";
 103     case VFIO_PCI_REQ_IRQ_INDEX:
 104         return "REQ";
 105     default:
 106         return NULL;
 107     }
 108 }
 109
 110 int vfio_set_irq_signaling(VFIODevice *vbasedev, int index, int subindex,
 111                            int action, int fd, Error **errp)
 112 {
 113     struct vfio_irq_set *irq_set;
 114     int argsz, ret = 0;
 115     const char *name;
 116     int32_t *pfd;
 117
 118     argsz = sizeof(*irq_set) + sizeof(*pfd);
 119
 120     irq_set = g_malloc0(argsz);
 121     irq_set->argsz = argsz;
 122     irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | action;
 123     irq_set->index = index;
 124     irq_set->start = subindex;
 125     irq_set->count = 1;
 126     pfd = (int32_t *)&irq_set->data;
 127     *pfd = fd;
 128
 129     if (ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
 130         ret = -errno;
 131     }
 132     g_free(irq_set);
 133
 134     if (!ret) {
 135         return 0;
 136     }
 137
 138     error_setg_errno(errp, -ret, "VFIO_DEVICE_SET_IRQS failure");
 139
 140     name = index_to_str(vbasedev, index);
 141     if (name) {
 142         error_prepend(errp, "%s-%d: ", name, subindex);
 143     } else {
 144         error_prepend(errp, "index %d-%d: ", index, subindex);
 145     }
 146     error_prepend(errp,
 147                   "Failed to %s %s eventfd signaling for interrupt ",
 148                   fd < 0 ? "tear down" : "set up", action_to_str(action));
 149     return ret;
 150 }
 151
 152 /*
 153  * IO Port/MMIO - Beware of the endians, VFIO is always little endian
 154  */
 155 void vfio_region_write(void *opaque, hwaddr addr,
 156                        uint64_t data, unsigned size)
 157 {
 158     VFIORegion *region = opaque;
 159     VFIODevice *vbasedev = region->vbasedev;
 160     union {
 161         uint8_t byte;
 162         uint16_t word;
 163         uint32_t dword;
 164         uint64_t qword;
 165     } buf;
 166
 167     switch (size) {
 168     case 1:
 169         buf.byte = data;
 170         break;
 171     case 2:
 172         buf.word = cpu_to_le16(data);
 173         break;
 174     case 4:
 175         buf.dword = cpu_to_le32(data);
 176         break;
 177     case 8:
 178         buf.qword = cpu_to_le64(data);
 179         break;
 180     default:
 181         hw_error("vfio: unsupported write size, %u bytes", size);
 182         break;
 183     }
 184
 185     if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
 186         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
 187                      ",%d) failed: %m",
 188                      __func__, vbasedev->name, region->nr,
 189                      addr, data, size);
 190     }
 191
 192     trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
 193
 194     /*
 195      * A read or write to a BAR always signals an INTx EOI.  This will
 196      * do nothing if not pending (including not in INTx mode).  We assume
 197      * that a BAR access is in response to an interrupt and that BAR
 198      * accesses will service the interrupt.  Unfortunately, we don't know
 199      * which access will service the interrupt, so we're potentially
 200      * getting quite a few host interrupts per guest interrupt.
 201      */
 202     vbasedev->ops->vfio_eoi(vbasedev);
 203 }
 204
 205 uint64_t vfio_region_read(void *opaque,
 206                           hwaddr addr, unsigned size)
 207 {
 208     VFIORegion *region = opaque;
 209     VFIODevice *vbasedev = region->vbasedev;
 210     union {
 211         uint8_t byte;
 212         uint16_t word;
 213         uint32_t dword;
 214         uint64_t qword;
 215     } buf;
 216     uint64_t data = 0;
 217
 218     if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
 219         error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
 220                      __func__, vbasedev->name, region->nr,
 221                      addr, size);
 222         return (uint64_t)-1;
 223     }
 224     switch (size) {
 225     case 1:
 226         data = buf.byte;
 227         break;
 228     case 2:
 229         data = le16_to_cpu(buf.word);
 230         break;
 231     case 4:
 232         data = le32_to_cpu(buf.dword);
 233         break;
 234     case 8:
 235         data = le64_to_cpu(buf.qword);
 236         break;
 237     default:
 238         hw_error("vfio: unsupported read size, %u bytes", size);
 239         break;
 240     }
 241
 242     trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data);
 243
 244     /* Same as write above */
 245     vbasedev->ops->vfio_eoi(vbasedev);
 246
 247     return data;
 248 }
 249
 250 const MemoryRegionOps vfio_region_ops = {
 251     .read = vfio_region_read,
 252     .write = vfio_region_write,
 253     .endianness = DEVICE_LITTLE_ENDIAN,
 254     .valid = {
 255         .min_access_size = 1,
 256         .max_access_size = 8,
 257     },
 258     .impl = {
 259         .min_access_size = 1,
 260         .max_access_size = 8,
 261     },
 262 };
 263
 264 int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size)
 265 {
 266     vbmap->pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size();
 267     vbmap->size = ROUND_UP(vbmap->pages, sizeof(__u64) * BITS_PER_BYTE) /
 268                                          BITS_PER_BYTE;
 269     vbmap->bitmap = g_try_malloc0(vbmap->size);
 270     if (!vbmap->bitmap) {
 271         return -ENOMEM;
 272     }
 273
 274     return 0;
 275 }
 276
 277 struct vfio_info_cap_header *
 278 vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id)
 279 {
 280     struct vfio_info_cap_header *hdr;
 281
 282     for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
 283         if (hdr->id == id) {
 284             return hdr;
 285         }
 286     }
 287
 288     return NULL;
 289 }
 290
 291 struct vfio_info_cap_header *
 292 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
 293 {
 294     if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
 295         return NULL;
 296     }
 297
 298     return vfio_get_cap((void *)info, info->cap_offset, id);
 299 }
 300
 301 struct vfio_info_cap_header *
 302 vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id)
 303 {
 304     if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) {
 305         return NULL;
 306     }
 307
 308     return vfio_get_cap((void *)info, info->cap_offset, id);
 309 }
 310
 311 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
 312                                           struct vfio_region_info *info)
 313 {
 314     struct vfio_info_cap_header *hdr;
 315     struct vfio_region_info_cap_sparse_mmap *sparse;
 316     int i, j;
 317
 318     hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP);
 319     if (!hdr) {
 320         return -ENODEV;
 321     }
 322
 323     sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header);
 324
 325     trace_vfio_region_sparse_mmap_header(region->vbasedev->name,
 326                                          region->nr, sparse->nr_areas);
 327
 328     region->mmaps = g_new0(VFIOMmap, sparse->nr_areas);
 329
 330     for (i = 0, j = 0; i < sparse->nr_areas; i++) {
 331         if (sparse->areas[i].size) {
 332             trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset,
 333                                             sparse->areas[i].offset +
 334                                             sparse->areas[i].size - 1);
 335             region->mmaps[j].offset = sparse->areas[i].offset;
 336             region->mmaps[j].size = sparse->areas[i].size;
 337             j++;
 338         }
 339     }
 340
 341     region->nr_mmaps = j;
 342     region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap));
 343
 344     return 0;
 345 }
 346
 347 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
 348                       int index, const char *name)
 349 {
 350     struct vfio_region_info *info;
 351     int ret;
 352
 353     ret = vfio_get_region_info(vbasedev, index, &info);
 354     if (ret) {
 355         return ret;
 356     }
 357
 358     region->vbasedev = vbasedev;
 359     region->flags = info->flags;
 360     region->size = info->size;
 361     region->fd_offset = info->offset;
 362     region->nr = index;
 363
 364     if (region->size) {
 365         region->mem = g_new0(MemoryRegion, 1);
 366         memory_region_init_io(region->mem, obj, &vfio_region_ops,
 367                               region, name, region->size);
 368
 369         if (!vbasedev->no_mmap &&
 370             region->flags & VFIO_REGION_INFO_FLAG_MMAP) {
 371
 372             ret = vfio_setup_region_sparse_mmaps(region, info);
 373
 374             if (ret) {
 375                 region->nr_mmaps = 1;
 376                 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
 377                 region->mmaps[0].offset = 0;
 378                 region->mmaps[0].size = region->size;
 379             }
 380         }
 381     }
 382
 383     g_free(info);
 384
 385     trace_vfio_region_setup(vbasedev->name, index, name,
 386                             region->flags, region->fd_offset, region->size);
 387     return 0;
 388 }
 389
 390 static void vfio_subregion_unmap(VFIORegion *region, int index)
 391 {
 392     trace_vfio_region_unmap(memory_region_name(&region->mmaps[index].mem),
 393                             region->mmaps[index].offset,
 394                             region->mmaps[index].offset +
 395                             region->mmaps[index].size - 1);
 396     memory_region_del_subregion(region->mem, &region->mmaps[index].mem);
 397     munmap(region->mmaps[index].mmap, region->mmaps[index].size);
 398     object_unparent(OBJECT(&region->mmaps[index].mem));
 399     region->mmaps[index].mmap = NULL;
 400 }
 401
 402 int vfio_region_mmap(VFIORegion *region)
 403 {
 404     int i, prot = 0;
 405     char *name;
 406
 407     if (!region->mem) {
 408         return 0;
 409     }
 410
 411     prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
 412     prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
 413
 414     for (i = 0; i < region->nr_mmaps; i++) {
 415         region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
 416                                      MAP_SHARED, region->vbasedev->fd,
 417                                      region->fd_offset +
 418                                      region->mmaps[i].offset);
 419         if (region->mmaps[i].mmap == MAP_FAILED) {
 420             int ret = -errno;
 421
 422             trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
 423                                          region->fd_offset +
 424                                          region->mmaps[i].offset,
 425                                          region->fd_offset +
 426                                          region->mmaps[i].offset +
 427                                          region->mmaps[i].size - 1, ret);
 428
 429             region->mmaps[i].mmap = NULL;
 430
 431             for (i--; i >= 0; i--) {
 432                 vfio_subregion_unmap(region, i);
 433             }
 434
 435             return ret;
 436         }
 437
 438         name = g_strdup_printf("%s mmaps[%d]",
 439                                memory_region_name(region->mem), i);
 440         memory_region_init_ram_device_ptr(&region->mmaps[i].mem,
 441                                           memory_region_owner(region->mem),
 442                                           name, region->mmaps[i].size,
 443                                           region->mmaps[i].mmap);
 444         g_free(name);
 445         memory_region_add_subregion(region->mem, region->mmaps[i].offset,
 446                                     &region->mmaps[i].mem);
 447
 448         trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
 449                                region->mmaps[i].offset,
 450                                region->mmaps[i].offset +
 451                                region->mmaps[i].size - 1);
 452     }
 453
 454     return 0;
 455 }
 456
 457 void vfio_region_unmap(VFIORegion *region)
 458 {
 459     int i;
 460
 461     if (!region->mem) {
 462         return;
 463     }
 464
 465     for (i = 0; i < region->nr_mmaps; i++) {
 466         if (region->mmaps[i].mmap) {
 467             vfio_subregion_unmap(region, i);
 468         }
 469     }
 470 }
 471
 472 void vfio_region_exit(VFIORegion *region)
 473 {
 474     int i;
 475
 476     if (!region->mem) {
 477         return;
 478     }
 479
 480     for (i = 0; i < region->nr_mmaps; i++) {
 481         if (region->mmaps[i].mmap) {
 482             memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
 483         }
 484     }
 485
 486     trace_vfio_region_exit(region->vbasedev->name, region->nr);
 487 }
 488
 489 void vfio_region_finalize(VFIORegion *region)
 490 {
 491     int i;
 492
 493     if (!region->mem) {
 494         return;
 495     }
 496
 497     for (i = 0; i < region->nr_mmaps; i++) {
 498         if (region->mmaps[i].mmap) {
 499             munmap(region->mmaps[i].mmap, region->mmaps[i].size);
 500             object_unparent(OBJECT(&region->mmaps[i].mem));
 501         }
 502     }
 503
 504     object_unparent(OBJECT(region->mem));
 505
 506     g_free(region->mem);
 507     g_free(region->mmaps);
 508
 509     trace_vfio_region_finalize(region->vbasedev->name, region->nr);
 510
 511     region->mem = NULL;
 512     region->mmaps = NULL;
 513     region->nr_mmaps = 0;
 514     region->size = 0;
 515     region->flags = 0;
 516     region->nr = 0;
 517 }
 518
 519 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
 520 {
 521     int i;
 522
 523     if (!region->mem) {
 524         return;
 525     }
 526
 527     for (i = 0; i < region->nr_mmaps; i++) {
 528         if (region->mmaps[i].mmap) {
 529             memory_region_set_enabled(&region->mmaps[i].mem, enabled);
 530         }
 531     }
 532
 533     trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
 534                                         enabled);
 535 }
 536
 537 int vfio_get_region_info(VFIODevice *vbasedev, int index,
 538                          struct vfio_region_info **info)
 539 {
 540     size_t argsz = sizeof(struct vfio_region_info);
 541
 542     *info = g_malloc0(argsz);
 543
 544     (*info)->index = index;
 545 retry:
 546     (*info)->argsz = argsz;
 547
 548     if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
 549         g_free(*info);
 550         *info = NULL;
 551         return -errno;
 552     }
 553
 554     if ((*info)->argsz > argsz) {
 555         argsz = (*info)->argsz;
 556         *info = g_realloc(*info, argsz);
 557
 558         goto retry;
 559     }
 560
 561     return 0;
 562 }
 563
 564 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
 565                              uint32_t subtype, struct vfio_region_info **info)
 566 {
 567     int i;
 568
 569     for (i = 0; i < vbasedev->num_regions; i++) {
 570         struct vfio_info_cap_header *hdr;
 571         struct vfio_region_info_cap_type *cap_type;
 572
 573         if (vfio_get_region_info(vbasedev, i, info)) {
 574             continue;
 575         }
 576
 577         hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
 578         if (!hdr) {
 579             g_free(*info);
 580             continue;
 581         }
 582
 583         cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
 584
 585         trace_vfio_get_dev_region(vbasedev->name, i,
 586                                   cap_type->type, cap_type->subtype);
 587
 588         if (cap_type->type == type && cap_type->subtype == subtype) {
 589             return 0;
 590         }
 591
 592         g_free(*info);
 593     }
 594
 595     *info = NULL;
 596     return -ENODEV;
 597 }
 598
 599 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
 600 {
 601     struct vfio_region_info *info = NULL;
 602     bool ret = false;
 603
 604     if (!vfio_get_region_info(vbasedev, region, &info)) {
 605         if (vfio_get_region_info_cap(info, cap_type)) {
 606             ret = true;
 607         }
 608         g_free(info);
 609     }
 610
 611     return ret;
 612 }
 613
 614 int vfio_device_get_name(VFIODevice *vbasedev, Error **errp)
 615 {
 616     struct stat st;
 617
 618     if (vbasedev->fd < 0) {
 619         if (stat(vbasedev->sysfsdev, &st) < 0) {
 620             error_setg_errno(errp, errno, "no such host device");
 621             error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev);
 622             return -errno;
 623         }
 624         /* User may specify a name, e.g: VFIO platform device */
 625         if (!vbasedev->name) {
 626             vbasedev->name = g_path_get_basename(vbasedev->sysfsdev);
 627         }
 628     } else {
 629         if (!vbasedev->iommufd) {
 630             error_setg(errp, "Use FD passing only with iommufd backend");
 631             return -EINVAL;
 632         }
 633         /*
 634          * Give a name with fd so any function printing out vbasedev->name
 635          * will not break.
 636          */
 637         if (!vbasedev->name) {
 638             vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd);
 639         }
 640     }
 641
 642     return 0;
 643 }
 644
 645 void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
 646 {
 647     int fd = monitor_fd_param(monitor_cur(), str, errp);
 648
 649     if (fd < 0) {
 650         error_prepend(errp, "Could not parse remote object fd %s:", str);
 651         return;
 652     }
 653     vbasedev->fd = fd;
 654 }