1 /* 2 * generic functions used by VFIO devices 3 * 4 * Copyright Red Hat, Inc. 2012 5 * 6 * Authors: 7 * Alex Williamson <alex.williamson@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 * Based on qemu-kvm device-assignment: 13 * Adapted for KVM by Qumranet. 14 * Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com) 15 * Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com) 16 * Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com) 17 * Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com) 18 * Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com) 19 */ 20 21 #include "qemu/osdep.h" 22 #include <sys/ioctl.h> 23 #ifdef CONFIG_KVM 24 #include <linux/kvm.h> 25 #endif 26 #include <linux/vfio.h> 27 28 #include "hw/vfio/vfio-common.h" 29 #include "hw/vfio/vfio.h" 30 #include "exec/address-spaces.h" 31 #include "exec/memory.h" 32 #include "exec/ram_addr.h" 33 #include "hw/hw.h" 34 #include "qemu/error-report.h" 35 #include "qemu/main-loop.h" 36 #include "qemu/range.h" 37 #include "sysemu/kvm.h" 38 #include "sysemu/reset.h" 39 #include "sysemu/runstate.h" 40 #include "trace.h" 41 #include "qapi/error.h" 42 #include "migration/migration.h" 43 44 VFIOGroupList vfio_group_list = 45 QLIST_HEAD_INITIALIZER(vfio_group_list); 46 static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces = 47 QLIST_HEAD_INITIALIZER(vfio_address_spaces); 48 49 #ifdef CONFIG_KVM 50 /* 51 * We have a single VFIO pseudo device per KVM VM. Once created it lives 52 * for the life of the VM. Closing the file descriptor only drops our 53 * reference to it and the device's reference to kvm. Therefore once 54 * initialized, this file descriptor is only released on QEMU exit and 55 * we'll re-use it should another vfio device be attached before then. 56 */ 57 static int vfio_kvm_device_fd = -1; 58 #endif 59 60 /* 61 * Common VFIO interrupt disable 62 */ 63 void vfio_disable_irqindex(VFIODevice *vbasedev, int index) 64 { 65 struct vfio_irq_set irq_set = { 66 .argsz = sizeof(irq_set), 67 .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER, 68 .index = index, 69 .start = 0, 70 .count = 0, 71 }; 72 73 ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set); 74 } 75 76 void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index) 77 { 78 struct vfio_irq_set irq_set = { 79 .argsz = sizeof(irq_set), 80 .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK, 81 .index = index, 82 .start = 0, 83 .count = 1, 84 }; 85 86 ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set); 87 } 88 89 void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index) 90 { 91 struct vfio_irq_set irq_set = { 92 .argsz = sizeof(irq_set), 93 .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK, 94 .index = index, 95 .start = 0, 96 .count = 1, 97 }; 98 99 ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set); 100 } 101 102 static inline const char *action_to_str(int action) 103 { 104 switch (action) { 105 case VFIO_IRQ_SET_ACTION_MASK: 106 return "MASK"; 107 case VFIO_IRQ_SET_ACTION_UNMASK: 108 return "UNMASK"; 109 case VFIO_IRQ_SET_ACTION_TRIGGER: 110 return "TRIGGER"; 111 default: 112 return "UNKNOWN ACTION"; 113 } 114 } 115 116 static const char *index_to_str(VFIODevice *vbasedev, int index) 117 { 118 if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) { 119 return NULL; 120 } 121 122 switch (index) { 123 case VFIO_PCI_INTX_IRQ_INDEX: 124 return "INTX"; 125 case VFIO_PCI_MSI_IRQ_INDEX: 126 return "MSI"; 127 case VFIO_PCI_MSIX_IRQ_INDEX: 128 return "MSIX"; 129 case VFIO_PCI_ERR_IRQ_INDEX: 130 return "ERR"; 131 case VFIO_PCI_REQ_IRQ_INDEX: 132 return "REQ"; 133 default: 134 return NULL; 135 } 136 } 137 138 static int vfio_ram_block_discard_disable(VFIOContainer *container, bool state) 139 { 140 switch (container->iommu_type) { 141 case VFIO_TYPE1v2_IOMMU: 142 case VFIO_TYPE1_IOMMU: 143 /* 144 * We support coordinated discarding of RAM via the RamDiscardManager. 145 */ 146 return ram_block_uncoordinated_discard_disable(state); 147 default: 148 /* 149 * VFIO_SPAPR_TCE_IOMMU most probably works just fine with 150 * RamDiscardManager, however, it is completely untested. 151 * 152 * VFIO_SPAPR_TCE_v2_IOMMU with "DMA memory preregistering" does 153 * completely the opposite of managing mapping/pinning dynamically as 154 * required by RamDiscardManager. We would have to special-case sections 155 * with a RamDiscardManager. 156 */ 157 return ram_block_discard_disable(state); 158 } 159 } 160 161 int vfio_set_irq_signaling(VFIODevice *vbasedev, int index, int subindex, 162 int action, int fd, Error **errp) 163 { 164 struct vfio_irq_set *irq_set; 165 int argsz, ret = 0; 166 const char *name; 167 int32_t *pfd; 168 169 argsz = sizeof(*irq_set) + sizeof(*pfd); 170 171 irq_set = g_malloc0(argsz); 172 irq_set->argsz = argsz; 173 irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | action; 174 irq_set->index = index; 175 irq_set->start = subindex; 176 irq_set->count = 1; 177 pfd = (int32_t *)&irq_set->data; 178 *pfd = fd; 179 180 if (ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) { 181 ret = -errno; 182 } 183 g_free(irq_set); 184 185 if (!ret) { 186 return 0; 187 } 188 189 error_setg_errno(errp, -ret, "VFIO_DEVICE_SET_IRQS failure"); 190 191 name = index_to_str(vbasedev, index); 192 if (name) { 193 error_prepend(errp, "%s-%d: ", name, subindex); 194 } else { 195 error_prepend(errp, "index %d-%d: ", index, subindex); 196 } 197 error_prepend(errp, 198 "Failed to %s %s eventfd signaling for interrupt ", 199 fd < 0 ? "tear down" : "set up", action_to_str(action)); 200 return ret; 201 } 202 203 /* 204 * IO Port/MMIO - Beware of the endians, VFIO is always little endian 205 */ 206 void vfio_region_write(void *opaque, hwaddr addr, 207 uint64_t data, unsigned size) 208 { 209 VFIORegion *region = opaque; 210 VFIODevice *vbasedev = region->vbasedev; 211 union { 212 uint8_t byte; 213 uint16_t word; 214 uint32_t dword; 215 uint64_t qword; 216 } buf; 217 218 switch (size) { 219 case 1: 220 buf.byte = data; 221 break; 222 case 2: 223 buf.word = cpu_to_le16(data); 224 break; 225 case 4: 226 buf.dword = cpu_to_le32(data); 227 break; 228 case 8: 229 buf.qword = cpu_to_le64(data); 230 break; 231 default: 232 hw_error("vfio: unsupported write size, %u bytes", size); 233 break; 234 } 235 236 if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) { 237 error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64 238 ",%d) failed: %m", 239 __func__, vbasedev->name, region->nr, 240 addr, data, size); 241 } 242 243 trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size); 244 245 /* 246 * A read or write to a BAR always signals an INTx EOI. This will 247 * do nothing if not pending (including not in INTx mode). We assume 248 * that a BAR access is in response to an interrupt and that BAR 249 * accesses will service the interrupt. Unfortunately, we don't know 250 * which access will service the interrupt, so we're potentially 251 * getting quite a few host interrupts per guest interrupt. 252 */ 253 vbasedev->ops->vfio_eoi(vbasedev); 254 } 255 256 uint64_t vfio_region_read(void *opaque, 257 hwaddr addr, unsigned size) 258 { 259 VFIORegion *region = opaque; 260 VFIODevice *vbasedev = region->vbasedev; 261 union { 262 uint8_t byte; 263 uint16_t word; 264 uint32_t dword; 265 uint64_t qword; 266 } buf; 267 uint64_t data = 0; 268 269 if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) { 270 error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m", 271 __func__, vbasedev->name, region->nr, 272 addr, size); 273 return (uint64_t)-1; 274 } 275 switch (size) { 276 case 1: 277 data = buf.byte; 278 break; 279 case 2: 280 data = le16_to_cpu(buf.word); 281 break; 282 case 4: 283 data = le32_to_cpu(buf.dword); 284 break; 285 case 8: 286 data = le64_to_cpu(buf.qword); 287 break; 288 default: 289 hw_error("vfio: unsupported read size, %u bytes", size); 290 break; 291 } 292 293 trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data); 294 295 /* Same as write above */ 296 vbasedev->ops->vfio_eoi(vbasedev); 297 298 return data; 299 } 300 301 const MemoryRegionOps vfio_region_ops = { 302 .read = vfio_region_read, 303 .write = vfio_region_write, 304 .endianness = DEVICE_LITTLE_ENDIAN, 305 .valid = { 306 .min_access_size = 1, 307 .max_access_size = 8, 308 }, 309 .impl = { 310 .min_access_size = 1, 311 .max_access_size = 8, 312 }, 313 }; 314 315 /* 316 * Device state interfaces 317 */ 318 319 bool vfio_mig_active(void) 320 { 321 VFIOGroup *group; 322 VFIODevice *vbasedev; 323 324 if (QLIST_EMPTY(&vfio_group_list)) { 325 return false; 326 } 327 328 QLIST_FOREACH(group, &vfio_group_list, next) { 329 QLIST_FOREACH(vbasedev, &group->device_list, next) { 330 if (vbasedev->migration_blocker) { 331 return false; 332 } 333 } 334 } 335 return true; 336 } 337 338 static bool vfio_devices_all_dirty_tracking(VFIOContainer *container) 339 { 340 VFIOGroup *group; 341 VFIODevice *vbasedev; 342 MigrationState *ms = migrate_get_current(); 343 344 if (!migration_is_setup_or_active(ms->state)) { 345 return false; 346 } 347 348 QLIST_FOREACH(group, &container->group_list, container_next) { 349 QLIST_FOREACH(vbasedev, &group->device_list, next) { 350 VFIOMigration *migration = vbasedev->migration; 351 352 if (!migration) { 353 return false; 354 } 355 356 if ((vbasedev->pre_copy_dirty_page_tracking == ON_OFF_AUTO_OFF) 357 && (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) { 358 return false; 359 } 360 } 361 } 362 return true; 363 } 364 365 static bool vfio_devices_all_running_and_saving(VFIOContainer *container) 366 { 367 VFIOGroup *group; 368 VFIODevice *vbasedev; 369 MigrationState *ms = migrate_get_current(); 370 371 if (!migration_is_setup_or_active(ms->state)) { 372 return false; 373 } 374 375 QLIST_FOREACH(group, &container->group_list, container_next) { 376 QLIST_FOREACH(vbasedev, &group->device_list, next) { 377 VFIOMigration *migration = vbasedev->migration; 378 379 if (!migration) { 380 return false; 381 } 382 383 if ((migration->device_state & VFIO_DEVICE_STATE_SAVING) && 384 (migration->device_state & VFIO_DEVICE_STATE_RUNNING)) { 385 continue; 386 } else { 387 return false; 388 } 389 } 390 } 391 return true; 392 } 393 394 static int vfio_dma_unmap_bitmap(VFIOContainer *container, 395 hwaddr iova, ram_addr_t size, 396 IOMMUTLBEntry *iotlb) 397 { 398 struct vfio_iommu_type1_dma_unmap *unmap; 399 struct vfio_bitmap *bitmap; 400 uint64_t pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size; 401 int ret; 402 403 unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap)); 404 405 unmap->argsz = sizeof(*unmap) + sizeof(*bitmap); 406 unmap->iova = iova; 407 unmap->size = size; 408 unmap->flags |= VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP; 409 bitmap = (struct vfio_bitmap *)&unmap->data; 410 411 /* 412 * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of 413 * qemu_real_host_page_size to mark those dirty. Hence set bitmap_pgsize 414 * to qemu_real_host_page_size. 415 */ 416 417 bitmap->pgsize = qemu_real_host_page_size; 418 bitmap->size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) / 419 BITS_PER_BYTE; 420 421 if (bitmap->size > container->max_dirty_bitmap_size) { 422 error_report("UNMAP: Size of bitmap too big 0x%"PRIx64, 423 (uint64_t)bitmap->size); 424 ret = -E2BIG; 425 goto unmap_exit; 426 } 427 428 bitmap->data = g_try_malloc0(bitmap->size); 429 if (!bitmap->data) { 430 ret = -ENOMEM; 431 goto unmap_exit; 432 } 433 434 ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap); 435 if (!ret) { 436 cpu_physical_memory_set_dirty_lebitmap((unsigned long *)bitmap->data, 437 iotlb->translated_addr, pages); 438 } else { 439 error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m"); 440 } 441 442 g_free(bitmap->data); 443 unmap_exit: 444 g_free(unmap); 445 return ret; 446 } 447 448 /* 449 * DMA - Mapping and unmapping for the "type1" IOMMU interface used on x86 450 */ 451 static int vfio_dma_unmap(VFIOContainer *container, 452 hwaddr iova, ram_addr_t size, 453 IOMMUTLBEntry *iotlb) 454 { 455 struct vfio_iommu_type1_dma_unmap unmap = { 456 .argsz = sizeof(unmap), 457 .flags = 0, 458 .iova = iova, 459 .size = size, 460 }; 461 462 if (iotlb && container->dirty_pages_supported && 463 vfio_devices_all_running_and_saving(container)) { 464 return vfio_dma_unmap_bitmap(container, iova, size, iotlb); 465 } 466 467 while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) { 468 /* 469 * The type1 backend has an off-by-one bug in the kernel (71a7d3d78e3c 470 * v4.15) where an overflow in its wrap-around check prevents us from 471 * unmapping the last page of the address space. Test for the error 472 * condition and re-try the unmap excluding the last page. The 473 * expectation is that we've never mapped the last page anyway and this 474 * unmap request comes via vIOMMU support which also makes it unlikely 475 * that this page is used. This bug was introduced well after type1 v2 476 * support was introduced, so we shouldn't need to test for v1. A fix 477 * is queued for kernel v5.0 so this workaround can be removed once 478 * affected kernels are sufficiently deprecated. 479 */ 480 if (errno == EINVAL && unmap.size && !(unmap.iova + unmap.size) && 481 container->iommu_type == VFIO_TYPE1v2_IOMMU) { 482 trace_vfio_dma_unmap_overflow_workaround(); 483 unmap.size -= 1ULL << ctz64(container->pgsizes); 484 continue; 485 } 486 error_report("VFIO_UNMAP_DMA failed: %s", strerror(errno)); 487 return -errno; 488 } 489 490 return 0; 491 } 492 493 static int vfio_dma_map(VFIOContainer *container, hwaddr iova, 494 ram_addr_t size, void *vaddr, bool readonly) 495 { 496 struct vfio_iommu_type1_dma_map map = { 497 .argsz = sizeof(map), 498 .flags = VFIO_DMA_MAP_FLAG_READ, 499 .vaddr = (__u64)(uintptr_t)vaddr, 500 .iova = iova, 501 .size = size, 502 }; 503 504 if (!readonly) { 505 map.flags |= VFIO_DMA_MAP_FLAG_WRITE; 506 } 507 508 /* 509 * Try the mapping, if it fails with EBUSY, unmap the region and try 510 * again. This shouldn't be necessary, but we sometimes see it in 511 * the VGA ROM space. 512 */ 513 if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 || 514 (errno == EBUSY && vfio_dma_unmap(container, iova, size, NULL) == 0 && 515 ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) { 516 return 0; 517 } 518 519 error_report("VFIO_MAP_DMA failed: %s", strerror(errno)); 520 return -errno; 521 } 522 523 static void vfio_host_win_add(VFIOContainer *container, 524 hwaddr min_iova, hwaddr max_iova, 525 uint64_t iova_pgsizes) 526 { 527 VFIOHostDMAWindow *hostwin; 528 529 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 530 if (ranges_overlap(hostwin->min_iova, 531 hostwin->max_iova - hostwin->min_iova + 1, 532 min_iova, 533 max_iova - min_iova + 1)) { 534 hw_error("%s: Overlapped IOMMU are not enabled", __func__); 535 } 536 } 537 538 hostwin = g_malloc0(sizeof(*hostwin)); 539 540 hostwin->min_iova = min_iova; 541 hostwin->max_iova = max_iova; 542 hostwin->iova_pgsizes = iova_pgsizes; 543 QLIST_INSERT_HEAD(&container->hostwin_list, hostwin, hostwin_next); 544 } 545 546 static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova, 547 hwaddr max_iova) 548 { 549 VFIOHostDMAWindow *hostwin; 550 551 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 552 if (hostwin->min_iova == min_iova && hostwin->max_iova == max_iova) { 553 QLIST_REMOVE(hostwin, hostwin_next); 554 return 0; 555 } 556 } 557 558 return -1; 559 } 560 561 static bool vfio_listener_skipped_section(MemoryRegionSection *section) 562 { 563 return (!memory_region_is_ram(section->mr) && 564 !memory_region_is_iommu(section->mr)) || 565 memory_region_is_protected(section->mr) || 566 /* 567 * Sizing an enabled 64-bit BAR can cause spurious mappings to 568 * addresses in the upper part of the 64-bit address space. These 569 * are never accessed by the CPU and beyond the address width of 570 * some IOMMU hardware. TODO: VFIO should tell us the IOMMU width. 571 */ 572 section->offset_within_address_space & (1ULL << 63); 573 } 574 575 /* Called with rcu_read_lock held. */ 576 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr, 577 ram_addr_t *ram_addr, bool *read_only) 578 { 579 MemoryRegion *mr; 580 hwaddr xlat; 581 hwaddr len = iotlb->addr_mask + 1; 582 bool writable = iotlb->perm & IOMMU_WO; 583 584 /* 585 * The IOMMU TLB entry we have just covers translation through 586 * this IOMMU to its immediate target. We need to translate 587 * it the rest of the way through to memory. 588 */ 589 mr = address_space_translate(&address_space_memory, 590 iotlb->translated_addr, 591 &xlat, &len, writable, 592 MEMTXATTRS_UNSPECIFIED); 593 if (!memory_region_is_ram(mr)) { 594 error_report("iommu map to non memory area %"HWADDR_PRIx"", 595 xlat); 596 return false; 597 } else if (memory_region_has_ram_discard_manager(mr)) { 598 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(mr); 599 MemoryRegionSection tmp = { 600 .mr = mr, 601 .offset_within_region = xlat, 602 .size = int128_make64(len), 603 }; 604 605 /* 606 * Malicious VMs can map memory into the IOMMU, which is expected 607 * to remain discarded. vfio will pin all pages, populating memory. 608 * Disallow that. vmstate priorities make sure any RamDiscardManager 609 * were already restored before IOMMUs are restored. 610 */ 611 if (!ram_discard_manager_is_populated(rdm, &tmp)) { 612 error_report("iommu map to discarded memory (e.g., unplugged via" 613 " virtio-mem): %"HWADDR_PRIx"", 614 iotlb->translated_addr); 615 return false; 616 } 617 618 /* 619 * Malicious VMs might trigger discarding of IOMMU-mapped memory. The 620 * pages will remain pinned inside vfio until unmapped, resulting in a 621 * higher memory consumption than expected. If memory would get 622 * populated again later, there would be an inconsistency between pages 623 * pinned by vfio and pages seen by QEMU. This is the case until 624 * unmapped from the IOMMU (e.g., during device reset). 625 * 626 * With malicious guests, we really only care about pinning more memory 627 * than expected. RLIMIT_MEMLOCK set for the user/process can never be 628 * exceeded and can be used to mitigate this problem. 629 */ 630 warn_report_once("Using vfio with vIOMMUs and coordinated discarding of" 631 " RAM (e.g., virtio-mem) works, however, malicious" 632 " guests can trigger pinning of more memory than" 633 " intended via an IOMMU. It's possible to mitigate " 634 " by setting/adjusting RLIMIT_MEMLOCK."); 635 } 636 637 /* 638 * Translation truncates length to the IOMMU page size, 639 * check that it did not truncate too much. 640 */ 641 if (len & iotlb->addr_mask) { 642 error_report("iommu has granularity incompatible with target AS"); 643 return false; 644 } 645 646 if (vaddr) { 647 *vaddr = memory_region_get_ram_ptr(mr) + xlat; 648 } 649 650 if (ram_addr) { 651 *ram_addr = memory_region_get_ram_addr(mr) + xlat; 652 } 653 654 if (read_only) { 655 *read_only = !writable || mr->readonly; 656 } 657 658 return true; 659 } 660 661 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 662 { 663 VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n); 664 VFIOContainer *container = giommu->container; 665 hwaddr iova = iotlb->iova + giommu->iommu_offset; 666 void *vaddr; 667 int ret; 668 669 trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP", 670 iova, iova + iotlb->addr_mask); 671 672 if (iotlb->target_as != &address_space_memory) { 673 error_report("Wrong target AS \"%s\", only system memory is allowed", 674 iotlb->target_as->name ? iotlb->target_as->name : "none"); 675 return; 676 } 677 678 rcu_read_lock(); 679 680 if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) { 681 bool read_only; 682 683 if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) { 684 goto out; 685 } 686 /* 687 * vaddr is only valid until rcu_read_unlock(). But after 688 * vfio_dma_map has set up the mapping the pages will be 689 * pinned by the kernel. This makes sure that the RAM backend 690 * of vaddr will always be there, even if the memory object is 691 * destroyed and its backing memory munmap-ed. 692 */ 693 ret = vfio_dma_map(container, iova, 694 iotlb->addr_mask + 1, vaddr, 695 read_only); 696 if (ret) { 697 error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", " 698 "0x%"HWADDR_PRIx", %p) = %d (%m)", 699 container, iova, 700 iotlb->addr_mask + 1, vaddr, ret); 701 } 702 } else { 703 ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb); 704 if (ret) { 705 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " 706 "0x%"HWADDR_PRIx") = %d (%m)", 707 container, iova, 708 iotlb->addr_mask + 1, ret); 709 } 710 } 711 out: 712 rcu_read_unlock(); 713 } 714 715 static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl, 716 MemoryRegionSection *section) 717 { 718 VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, 719 listener); 720 const hwaddr size = int128_get64(section->size); 721 const hwaddr iova = section->offset_within_address_space; 722 int ret; 723 724 /* Unmap with a single call. */ 725 ret = vfio_dma_unmap(vrdl->container, iova, size , NULL); 726 if (ret) { 727 error_report("%s: vfio_dma_unmap() failed: %s", __func__, 728 strerror(-ret)); 729 } 730 } 731 732 static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl, 733 MemoryRegionSection *section) 734 { 735 VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, 736 listener); 737 const hwaddr end = section->offset_within_region + 738 int128_get64(section->size); 739 hwaddr start, next, iova; 740 void *vaddr; 741 int ret; 742 743 /* 744 * Map in (aligned within memory region) minimum granularity, so we can 745 * unmap in minimum granularity later. 746 */ 747 for (start = section->offset_within_region; start < end; start = next) { 748 next = ROUND_UP(start + 1, vrdl->granularity); 749 next = MIN(next, end); 750 751 iova = start - section->offset_within_region + 752 section->offset_within_address_space; 753 vaddr = memory_region_get_ram_ptr(section->mr) + start; 754 755 ret = vfio_dma_map(vrdl->container, iova, next - start, 756 vaddr, section->readonly); 757 if (ret) { 758 /* Rollback */ 759 vfio_ram_discard_notify_discard(rdl, section); 760 return ret; 761 } 762 } 763 return 0; 764 } 765 766 static void vfio_register_ram_discard_listener(VFIOContainer *container, 767 MemoryRegionSection *section) 768 { 769 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 770 VFIORamDiscardListener *vrdl; 771 772 /* Ignore some corner cases not relevant in practice. */ 773 g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE)); 774 g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space, 775 TARGET_PAGE_SIZE)); 776 g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE)); 777 778 vrdl = g_new0(VFIORamDiscardListener, 1); 779 vrdl->container = container; 780 vrdl->mr = section->mr; 781 vrdl->offset_within_address_space = section->offset_within_address_space; 782 vrdl->size = int128_get64(section->size); 783 vrdl->granularity = ram_discard_manager_get_min_granularity(rdm, 784 section->mr); 785 786 g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity)); 787 g_assert(container->pgsizes && 788 vrdl->granularity >= 1ULL << ctz64(container->pgsizes)); 789 790 ram_discard_listener_init(&vrdl->listener, 791 vfio_ram_discard_notify_populate, 792 vfio_ram_discard_notify_discard, true); 793 ram_discard_manager_register_listener(rdm, &vrdl->listener, section); 794 QLIST_INSERT_HEAD(&container->vrdl_list, vrdl, next); 795 796 /* 797 * Sanity-check if we have a theoretically problematic setup where we could 798 * exceed the maximum number of possible DMA mappings over time. We assume 799 * that each mapped section in the same address space as a RamDiscardManager 800 * section consumes exactly one DMA mapping, with the exception of 801 * RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections 802 * in the same address space as RamDiscardManager sections. 803 * 804 * We assume that each section in the address space consumes one memslot. 805 * We take the number of KVM memory slots as a best guess for the maximum 806 * number of sections in the address space we could have over time, 807 * also consuming DMA mappings. 808 */ 809 if (container->dma_max_mappings) { 810 unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512; 811 812 #ifdef CONFIG_KVM 813 if (kvm_enabled()) { 814 max_memslots = kvm_get_max_memslots(); 815 } 816 #endif 817 818 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 819 hwaddr start, end; 820 821 start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space, 822 vrdl->granularity); 823 end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size, 824 vrdl->granularity); 825 vrdl_mappings += (end - start) / vrdl->granularity; 826 vrdl_count++; 827 } 828 829 if (vrdl_mappings + max_memslots - vrdl_count > 830 container->dma_max_mappings) { 831 warn_report("%s: possibly running out of DMA mappings. E.g., try" 832 " increasing the 'block-size' of virtio-mem devies." 833 " Maximum possible DMA mappings: %d, Maximum possible" 834 " memslots: %d", __func__, container->dma_max_mappings, 835 max_memslots); 836 } 837 } 838 } 839 840 static void vfio_unregister_ram_discard_listener(VFIOContainer *container, 841 MemoryRegionSection *section) 842 { 843 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 844 VFIORamDiscardListener *vrdl = NULL; 845 846 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 847 if (vrdl->mr == section->mr && 848 vrdl->offset_within_address_space == 849 section->offset_within_address_space) { 850 break; 851 } 852 } 853 854 if (!vrdl) { 855 hw_error("vfio: Trying to unregister missing RAM discard listener"); 856 } 857 858 ram_discard_manager_unregister_listener(rdm, &vrdl->listener); 859 QLIST_REMOVE(vrdl, next); 860 g_free(vrdl); 861 } 862 863 static void vfio_listener_region_add(MemoryListener *listener, 864 MemoryRegionSection *section) 865 { 866 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 867 hwaddr iova, end; 868 Int128 llend, llsize; 869 void *vaddr; 870 int ret; 871 VFIOHostDMAWindow *hostwin; 872 bool hostwin_found; 873 Error *err = NULL; 874 875 if (vfio_listener_skipped_section(section)) { 876 trace_vfio_listener_region_add_skip( 877 section->offset_within_address_space, 878 section->offset_within_address_space + 879 int128_get64(int128_sub(section->size, int128_one()))); 880 return; 881 } 882 883 if (unlikely((section->offset_within_address_space & 884 ~qemu_real_host_page_mask) != 885 (section->offset_within_region & ~qemu_real_host_page_mask))) { 886 error_report("%s received unaligned region", __func__); 887 return; 888 } 889 890 iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space); 891 llend = int128_make64(section->offset_within_address_space); 892 llend = int128_add(llend, section->size); 893 llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask)); 894 895 if (int128_ge(int128_make64(iova), llend)) { 896 return; 897 } 898 end = int128_get64(int128_sub(llend, int128_one())); 899 900 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 901 hwaddr pgsize = 0; 902 903 /* For now intersections are not allowed, we may relax this later */ 904 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 905 if (ranges_overlap(hostwin->min_iova, 906 hostwin->max_iova - hostwin->min_iova + 1, 907 section->offset_within_address_space, 908 int128_get64(section->size))) { 909 error_setg(&err, 910 "region [0x%"PRIx64",0x%"PRIx64"] overlaps with existing" 911 "host DMA window [0x%"PRIx64",0x%"PRIx64"]", 912 section->offset_within_address_space, 913 section->offset_within_address_space + 914 int128_get64(section->size) - 1, 915 hostwin->min_iova, hostwin->max_iova); 916 goto fail; 917 } 918 } 919 920 ret = vfio_spapr_create_window(container, section, &pgsize); 921 if (ret) { 922 error_setg_errno(&err, -ret, "Failed to create SPAPR window"); 923 goto fail; 924 } 925 926 vfio_host_win_add(container, section->offset_within_address_space, 927 section->offset_within_address_space + 928 int128_get64(section->size) - 1, pgsize); 929 #ifdef CONFIG_KVM 930 if (kvm_enabled()) { 931 VFIOGroup *group; 932 IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr); 933 struct kvm_vfio_spapr_tce param; 934 struct kvm_device_attr attr = { 935 .group = KVM_DEV_VFIO_GROUP, 936 .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE, 937 .addr = (uint64_t)(unsigned long)¶m, 938 }; 939 940 if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD, 941 ¶m.tablefd)) { 942 QLIST_FOREACH(group, &container->group_list, container_next) { 943 param.groupfd = group->fd; 944 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 945 error_report("vfio: failed to setup fd %d " 946 "for a group with fd %d: %s", 947 param.tablefd, param.groupfd, 948 strerror(errno)); 949 return; 950 } 951 trace_vfio_spapr_group_attach(param.groupfd, param.tablefd); 952 } 953 } 954 } 955 #endif 956 } 957 958 hostwin_found = false; 959 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 960 if (hostwin->min_iova <= iova && end <= hostwin->max_iova) { 961 hostwin_found = true; 962 break; 963 } 964 } 965 966 if (!hostwin_found) { 967 error_setg(&err, "Container %p can't map guest IOVA region" 968 " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, container, iova, end); 969 goto fail; 970 } 971 972 memory_region_ref(section->mr); 973 974 if (memory_region_is_iommu(section->mr)) { 975 VFIOGuestIOMMU *giommu; 976 IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr); 977 int iommu_idx; 978 979 trace_vfio_listener_region_add_iommu(iova, end); 980 /* 981 * FIXME: For VFIO iommu types which have KVM acceleration to 982 * avoid bouncing all map/unmaps through qemu this way, this 983 * would be the right place to wire that up (tell the KVM 984 * device emulation the VFIO iommu handles to use). 985 */ 986 giommu = g_malloc0(sizeof(*giommu)); 987 giommu->iommu = iommu_mr; 988 giommu->iommu_offset = section->offset_within_address_space - 989 section->offset_within_region; 990 giommu->container = container; 991 llend = int128_add(int128_make64(section->offset_within_region), 992 section->size); 993 llend = int128_sub(llend, int128_one()); 994 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 995 MEMTXATTRS_UNSPECIFIED); 996 iommu_notifier_init(&giommu->n, vfio_iommu_map_notify, 997 IOMMU_NOTIFIER_IOTLB_EVENTS, 998 section->offset_within_region, 999 int128_get64(llend), 1000 iommu_idx); 1001 1002 ret = memory_region_iommu_set_page_size_mask(giommu->iommu, 1003 container->pgsizes, 1004 &err); 1005 if (ret) { 1006 g_free(giommu); 1007 goto fail; 1008 } 1009 1010 ret = memory_region_register_iommu_notifier(section->mr, &giommu->n, 1011 &err); 1012 if (ret) { 1013 g_free(giommu); 1014 goto fail; 1015 } 1016 QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next); 1017 memory_region_iommu_replay(giommu->iommu, &giommu->n); 1018 1019 return; 1020 } 1021 1022 /* Here we assume that memory_region_is_ram(section->mr)==true */ 1023 1024 /* 1025 * For RAM memory regions with a RamDiscardManager, we only want to map the 1026 * actually populated parts - and update the mapping whenever we're notified 1027 * about changes. 1028 */ 1029 if (memory_region_has_ram_discard_manager(section->mr)) { 1030 vfio_register_ram_discard_listener(container, section); 1031 return; 1032 } 1033 1034 vaddr = memory_region_get_ram_ptr(section->mr) + 1035 section->offset_within_region + 1036 (iova - section->offset_within_address_space); 1037 1038 trace_vfio_listener_region_add_ram(iova, end, vaddr); 1039 1040 llsize = int128_sub(llend, int128_make64(iova)); 1041 1042 if (memory_region_is_ram_device(section->mr)) { 1043 hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1; 1044 1045 if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) { 1046 trace_vfio_listener_region_add_no_dma_map( 1047 memory_region_name(section->mr), 1048 section->offset_within_address_space, 1049 int128_getlo(section->size), 1050 pgmask + 1); 1051 return; 1052 } 1053 } 1054 1055 ret = vfio_dma_map(container, iova, int128_get64(llsize), 1056 vaddr, section->readonly); 1057 if (ret) { 1058 error_setg(&err, "vfio_dma_map(%p, 0x%"HWADDR_PRIx", " 1059 "0x%"HWADDR_PRIx", %p) = %d (%m)", 1060 container, iova, int128_get64(llsize), vaddr, ret); 1061 if (memory_region_is_ram_device(section->mr)) { 1062 /* Allow unexpected mappings not to be fatal for RAM devices */ 1063 error_report_err(err); 1064 return; 1065 } 1066 goto fail; 1067 } 1068 1069 return; 1070 1071 fail: 1072 if (memory_region_is_ram_device(section->mr)) { 1073 error_report("failed to vfio_dma_map. pci p2p may not work"); 1074 return; 1075 } 1076 /* 1077 * On the initfn path, store the first error in the container so we 1078 * can gracefully fail. Runtime, there's not much we can do other 1079 * than throw a hardware error. 1080 */ 1081 if (!container->initialized) { 1082 if (!container->error) { 1083 error_propagate_prepend(&container->error, err, 1084 "Region %s: ", 1085 memory_region_name(section->mr)); 1086 } else { 1087 error_free(err); 1088 } 1089 } else { 1090 error_report_err(err); 1091 hw_error("vfio: DMA mapping failed, unable to continue"); 1092 } 1093 } 1094 1095 static void vfio_listener_region_del(MemoryListener *listener, 1096 MemoryRegionSection *section) 1097 { 1098 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1099 hwaddr iova, end; 1100 Int128 llend, llsize; 1101 int ret; 1102 bool try_unmap = true; 1103 1104 if (vfio_listener_skipped_section(section)) { 1105 trace_vfio_listener_region_del_skip( 1106 section->offset_within_address_space, 1107 section->offset_within_address_space + 1108 int128_get64(int128_sub(section->size, int128_one()))); 1109 return; 1110 } 1111 1112 if (unlikely((section->offset_within_address_space & 1113 ~qemu_real_host_page_mask) != 1114 (section->offset_within_region & ~qemu_real_host_page_mask))) { 1115 error_report("%s received unaligned region", __func__); 1116 return; 1117 } 1118 1119 if (memory_region_is_iommu(section->mr)) { 1120 VFIOGuestIOMMU *giommu; 1121 1122 QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { 1123 if (MEMORY_REGION(giommu->iommu) == section->mr && 1124 giommu->n.start == section->offset_within_region) { 1125 memory_region_unregister_iommu_notifier(section->mr, 1126 &giommu->n); 1127 QLIST_REMOVE(giommu, giommu_next); 1128 g_free(giommu); 1129 break; 1130 } 1131 } 1132 1133 /* 1134 * FIXME: We assume the one big unmap below is adequate to 1135 * remove any individual page mappings in the IOMMU which 1136 * might have been copied into VFIO. This works for a page table 1137 * based IOMMU where a big unmap flattens a large range of IO-PTEs. 1138 * That may not be true for all IOMMU types. 1139 */ 1140 } 1141 1142 iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space); 1143 llend = int128_make64(section->offset_within_address_space); 1144 llend = int128_add(llend, section->size); 1145 llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask)); 1146 1147 if (int128_ge(int128_make64(iova), llend)) { 1148 return; 1149 } 1150 end = int128_get64(int128_sub(llend, int128_one())); 1151 1152 llsize = int128_sub(llend, int128_make64(iova)); 1153 1154 trace_vfio_listener_region_del(iova, end); 1155 1156 if (memory_region_is_ram_device(section->mr)) { 1157 hwaddr pgmask; 1158 VFIOHostDMAWindow *hostwin; 1159 bool hostwin_found = false; 1160 1161 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 1162 if (hostwin->min_iova <= iova && end <= hostwin->max_iova) { 1163 hostwin_found = true; 1164 break; 1165 } 1166 } 1167 assert(hostwin_found); /* or region_add() would have failed */ 1168 1169 pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1; 1170 try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask)); 1171 } else if (memory_region_has_ram_discard_manager(section->mr)) { 1172 vfio_unregister_ram_discard_listener(container, section); 1173 /* Unregistering will trigger an unmap. */ 1174 try_unmap = false; 1175 } 1176 1177 if (try_unmap) { 1178 if (int128_eq(llsize, int128_2_64())) { 1179 /* The unmap ioctl doesn't accept a full 64-bit span. */ 1180 llsize = int128_rshift(llsize, 1); 1181 ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL); 1182 if (ret) { 1183 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " 1184 "0x%"HWADDR_PRIx") = %d (%m)", 1185 container, iova, int128_get64(llsize), ret); 1186 } 1187 iova += int128_get64(llsize); 1188 } 1189 ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL); 1190 if (ret) { 1191 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " 1192 "0x%"HWADDR_PRIx") = %d (%m)", 1193 container, iova, int128_get64(llsize), ret); 1194 } 1195 } 1196 1197 memory_region_unref(section->mr); 1198 1199 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1200 vfio_spapr_remove_window(container, 1201 section->offset_within_address_space); 1202 if (vfio_host_win_del(container, 1203 section->offset_within_address_space, 1204 section->offset_within_address_space + 1205 int128_get64(section->size) - 1) < 0) { 1206 hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx, 1207 __func__, section->offset_within_address_space); 1208 } 1209 } 1210 } 1211 1212 static void vfio_set_dirty_page_tracking(VFIOContainer *container, bool start) 1213 { 1214 int ret; 1215 struct vfio_iommu_type1_dirty_bitmap dirty = { 1216 .argsz = sizeof(dirty), 1217 }; 1218 1219 if (start) { 1220 dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START; 1221 } else { 1222 dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP; 1223 } 1224 1225 ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty); 1226 if (ret) { 1227 error_report("Failed to set dirty tracking flag 0x%x errno: %d", 1228 dirty.flags, errno); 1229 } 1230 } 1231 1232 static void vfio_listener_log_global_start(MemoryListener *listener) 1233 { 1234 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1235 1236 vfio_set_dirty_page_tracking(container, true); 1237 } 1238 1239 static void vfio_listener_log_global_stop(MemoryListener *listener) 1240 { 1241 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1242 1243 vfio_set_dirty_page_tracking(container, false); 1244 } 1245 1246 static int vfio_get_dirty_bitmap(VFIOContainer *container, uint64_t iova, 1247 uint64_t size, ram_addr_t ram_addr) 1248 { 1249 struct vfio_iommu_type1_dirty_bitmap *dbitmap; 1250 struct vfio_iommu_type1_dirty_bitmap_get *range; 1251 uint64_t pages; 1252 int ret; 1253 1254 dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range)); 1255 1256 dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range); 1257 dbitmap->flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP; 1258 range = (struct vfio_iommu_type1_dirty_bitmap_get *)&dbitmap->data; 1259 range->iova = iova; 1260 range->size = size; 1261 1262 /* 1263 * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of 1264 * qemu_real_host_page_size to mark those dirty. Hence set bitmap's pgsize 1265 * to qemu_real_host_page_size. 1266 */ 1267 range->bitmap.pgsize = qemu_real_host_page_size; 1268 1269 pages = REAL_HOST_PAGE_ALIGN(range->size) / qemu_real_host_page_size; 1270 range->bitmap.size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) / 1271 BITS_PER_BYTE; 1272 range->bitmap.data = g_try_malloc0(range->bitmap.size); 1273 if (!range->bitmap.data) { 1274 ret = -ENOMEM; 1275 goto err_out; 1276 } 1277 1278 ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap); 1279 if (ret) { 1280 error_report("Failed to get dirty bitmap for iova: 0x%"PRIx64 1281 " size: 0x%"PRIx64" err: %d", (uint64_t)range->iova, 1282 (uint64_t)range->size, errno); 1283 goto err_out; 1284 } 1285 1286 cpu_physical_memory_set_dirty_lebitmap((unsigned long *)range->bitmap.data, 1287 ram_addr, pages); 1288 1289 trace_vfio_get_dirty_bitmap(container->fd, range->iova, range->size, 1290 range->bitmap.size, ram_addr); 1291 err_out: 1292 g_free(range->bitmap.data); 1293 g_free(dbitmap); 1294 1295 return ret; 1296 } 1297 1298 typedef struct { 1299 IOMMUNotifier n; 1300 VFIOGuestIOMMU *giommu; 1301 } vfio_giommu_dirty_notifier; 1302 1303 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 1304 { 1305 vfio_giommu_dirty_notifier *gdn = container_of(n, 1306 vfio_giommu_dirty_notifier, n); 1307 VFIOGuestIOMMU *giommu = gdn->giommu; 1308 VFIOContainer *container = giommu->container; 1309 hwaddr iova = iotlb->iova + giommu->iommu_offset; 1310 ram_addr_t translated_addr; 1311 1312 trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask); 1313 1314 if (iotlb->target_as != &address_space_memory) { 1315 error_report("Wrong target AS \"%s\", only system memory is allowed", 1316 iotlb->target_as->name ? iotlb->target_as->name : "none"); 1317 return; 1318 } 1319 1320 rcu_read_lock(); 1321 if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) { 1322 int ret; 1323 1324 ret = vfio_get_dirty_bitmap(container, iova, iotlb->addr_mask + 1, 1325 translated_addr); 1326 if (ret) { 1327 error_report("vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", " 1328 "0x%"HWADDR_PRIx") = %d (%m)", 1329 container, iova, 1330 iotlb->addr_mask + 1, ret); 1331 } 1332 } 1333 rcu_read_unlock(); 1334 } 1335 1336 static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section, 1337 void *opaque) 1338 { 1339 const hwaddr size = int128_get64(section->size); 1340 const hwaddr iova = section->offset_within_address_space; 1341 const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) + 1342 section->offset_within_region; 1343 VFIORamDiscardListener *vrdl = opaque; 1344 1345 /* 1346 * Sync the whole mapped region (spanning multiple individual mappings) 1347 * in one go. 1348 */ 1349 return vfio_get_dirty_bitmap(vrdl->container, iova, size, ram_addr); 1350 } 1351 1352 static int vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainer *container, 1353 MemoryRegionSection *section) 1354 { 1355 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 1356 VFIORamDiscardListener *vrdl = NULL; 1357 1358 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 1359 if (vrdl->mr == section->mr && 1360 vrdl->offset_within_address_space == 1361 section->offset_within_address_space) { 1362 break; 1363 } 1364 } 1365 1366 if (!vrdl) { 1367 hw_error("vfio: Trying to sync missing RAM discard listener"); 1368 } 1369 1370 /* 1371 * We only want/can synchronize the bitmap for actually mapped parts - 1372 * which correspond to populated parts. Replay all populated parts. 1373 */ 1374 return ram_discard_manager_replay_populated(rdm, section, 1375 vfio_ram_discard_get_dirty_bitmap, 1376 &vrdl); 1377 } 1378 1379 static int vfio_sync_dirty_bitmap(VFIOContainer *container, 1380 MemoryRegionSection *section) 1381 { 1382 ram_addr_t ram_addr; 1383 1384 if (memory_region_is_iommu(section->mr)) { 1385 VFIOGuestIOMMU *giommu; 1386 1387 QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { 1388 if (MEMORY_REGION(giommu->iommu) == section->mr && 1389 giommu->n.start == section->offset_within_region) { 1390 Int128 llend; 1391 vfio_giommu_dirty_notifier gdn = { .giommu = giommu }; 1392 int idx = memory_region_iommu_attrs_to_index(giommu->iommu, 1393 MEMTXATTRS_UNSPECIFIED); 1394 1395 llend = int128_add(int128_make64(section->offset_within_region), 1396 section->size); 1397 llend = int128_sub(llend, int128_one()); 1398 1399 iommu_notifier_init(&gdn.n, 1400 vfio_iommu_map_dirty_notify, 1401 IOMMU_NOTIFIER_MAP, 1402 section->offset_within_region, 1403 int128_get64(llend), 1404 idx); 1405 memory_region_iommu_replay(giommu->iommu, &gdn.n); 1406 break; 1407 } 1408 } 1409 return 0; 1410 } else if (memory_region_has_ram_discard_manager(section->mr)) { 1411 return vfio_sync_ram_discard_listener_dirty_bitmap(container, section); 1412 } 1413 1414 ram_addr = memory_region_get_ram_addr(section->mr) + 1415 section->offset_within_region; 1416 1417 return vfio_get_dirty_bitmap(container, 1418 REAL_HOST_PAGE_ALIGN(section->offset_within_address_space), 1419 int128_get64(section->size), ram_addr); 1420 } 1421 1422 static void vfio_listener_log_sync(MemoryListener *listener, 1423 MemoryRegionSection *section) 1424 { 1425 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1426 1427 if (vfio_listener_skipped_section(section) || 1428 !container->dirty_pages_supported) { 1429 return; 1430 } 1431 1432 if (vfio_devices_all_dirty_tracking(container)) { 1433 vfio_sync_dirty_bitmap(container, section); 1434 } 1435 } 1436 1437 static const MemoryListener vfio_memory_listener = { 1438 .region_add = vfio_listener_region_add, 1439 .region_del = vfio_listener_region_del, 1440 .log_global_start = vfio_listener_log_global_start, 1441 .log_global_stop = vfio_listener_log_global_stop, 1442 .log_sync = vfio_listener_log_sync, 1443 }; 1444 1445 static void vfio_listener_release(VFIOContainer *container) 1446 { 1447 memory_listener_unregister(&container->listener); 1448 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1449 memory_listener_unregister(&container->prereg_listener); 1450 } 1451 } 1452 1453 static struct vfio_info_cap_header * 1454 vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id) 1455 { 1456 struct vfio_info_cap_header *hdr; 1457 1458 for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) { 1459 if (hdr->id == id) { 1460 return hdr; 1461 } 1462 } 1463 1464 return NULL; 1465 } 1466 1467 struct vfio_info_cap_header * 1468 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id) 1469 { 1470 if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) { 1471 return NULL; 1472 } 1473 1474 return vfio_get_cap((void *)info, info->cap_offset, id); 1475 } 1476 1477 static struct vfio_info_cap_header * 1478 vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) 1479 { 1480 if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { 1481 return NULL; 1482 } 1483 1484 return vfio_get_cap((void *)info, info->cap_offset, id); 1485 } 1486 1487 struct vfio_info_cap_header * 1488 vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id) 1489 { 1490 if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) { 1491 return NULL; 1492 } 1493 1494 return vfio_get_cap((void *)info, info->cap_offset, id); 1495 } 1496 1497 bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info, 1498 unsigned int *avail) 1499 { 1500 struct vfio_info_cap_header *hdr; 1501 struct vfio_iommu_type1_info_dma_avail *cap; 1502 1503 /* If the capability cannot be found, assume no DMA limiting */ 1504 hdr = vfio_get_iommu_type1_info_cap(info, 1505 VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL); 1506 if (hdr == NULL) { 1507 return false; 1508 } 1509 1510 if (avail != NULL) { 1511 cap = (void *) hdr; 1512 *avail = cap->avail; 1513 } 1514 1515 return true; 1516 } 1517 1518 static int vfio_setup_region_sparse_mmaps(VFIORegion *region, 1519 struct vfio_region_info *info) 1520 { 1521 struct vfio_info_cap_header *hdr; 1522 struct vfio_region_info_cap_sparse_mmap *sparse; 1523 int i, j; 1524 1525 hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP); 1526 if (!hdr) { 1527 return -ENODEV; 1528 } 1529 1530 sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header); 1531 1532 trace_vfio_region_sparse_mmap_header(region->vbasedev->name, 1533 region->nr, sparse->nr_areas); 1534 1535 region->mmaps = g_new0(VFIOMmap, sparse->nr_areas); 1536 1537 for (i = 0, j = 0; i < sparse->nr_areas; i++) { 1538 trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset, 1539 sparse->areas[i].offset + 1540 sparse->areas[i].size); 1541 1542 if (sparse->areas[i].size) { 1543 region->mmaps[j].offset = sparse->areas[i].offset; 1544 region->mmaps[j].size = sparse->areas[i].size; 1545 j++; 1546 } 1547 } 1548 1549 region->nr_mmaps = j; 1550 region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap)); 1551 1552 return 0; 1553 } 1554 1555 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region, 1556 int index, const char *name) 1557 { 1558 struct vfio_region_info *info; 1559 int ret; 1560 1561 ret = vfio_get_region_info(vbasedev, index, &info); 1562 if (ret) { 1563 return ret; 1564 } 1565 1566 region->vbasedev = vbasedev; 1567 region->flags = info->flags; 1568 region->size = info->size; 1569 region->fd_offset = info->offset; 1570 region->nr = index; 1571 1572 if (region->size) { 1573 region->mem = g_new0(MemoryRegion, 1); 1574 memory_region_init_io(region->mem, obj, &vfio_region_ops, 1575 region, name, region->size); 1576 1577 if (!vbasedev->no_mmap && 1578 region->flags & VFIO_REGION_INFO_FLAG_MMAP) { 1579 1580 ret = vfio_setup_region_sparse_mmaps(region, info); 1581 1582 if (ret) { 1583 region->nr_mmaps = 1; 1584 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps); 1585 region->mmaps[0].offset = 0; 1586 region->mmaps[0].size = region->size; 1587 } 1588 } 1589 } 1590 1591 g_free(info); 1592 1593 trace_vfio_region_setup(vbasedev->name, index, name, 1594 region->flags, region->fd_offset, region->size); 1595 return 0; 1596 } 1597 1598 static void vfio_subregion_unmap(VFIORegion *region, int index) 1599 { 1600 trace_vfio_region_unmap(memory_region_name(®ion->mmaps[index].mem), 1601 region->mmaps[index].offset, 1602 region->mmaps[index].offset + 1603 region->mmaps[index].size - 1); 1604 memory_region_del_subregion(region->mem, ®ion->mmaps[index].mem); 1605 munmap(region->mmaps[index].mmap, region->mmaps[index].size); 1606 object_unparent(OBJECT(®ion->mmaps[index].mem)); 1607 region->mmaps[index].mmap = NULL; 1608 } 1609 1610 int vfio_region_mmap(VFIORegion *region) 1611 { 1612 int i, prot = 0; 1613 char *name; 1614 1615 if (!region->mem) { 1616 return 0; 1617 } 1618 1619 prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0; 1620 prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0; 1621 1622 for (i = 0; i < region->nr_mmaps; i++) { 1623 region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot, 1624 MAP_SHARED, region->vbasedev->fd, 1625 region->fd_offset + 1626 region->mmaps[i].offset); 1627 if (region->mmaps[i].mmap == MAP_FAILED) { 1628 int ret = -errno; 1629 1630 trace_vfio_region_mmap_fault(memory_region_name(region->mem), i, 1631 region->fd_offset + 1632 region->mmaps[i].offset, 1633 region->fd_offset + 1634 region->mmaps[i].offset + 1635 region->mmaps[i].size - 1, ret); 1636 1637 region->mmaps[i].mmap = NULL; 1638 1639 for (i--; i >= 0; i--) { 1640 vfio_subregion_unmap(region, i); 1641 } 1642 1643 return ret; 1644 } 1645 1646 name = g_strdup_printf("%s mmaps[%d]", 1647 memory_region_name(region->mem), i); 1648 memory_region_init_ram_device_ptr(®ion->mmaps[i].mem, 1649 memory_region_owner(region->mem), 1650 name, region->mmaps[i].size, 1651 region->mmaps[i].mmap); 1652 g_free(name); 1653 memory_region_add_subregion(region->mem, region->mmaps[i].offset, 1654 ®ion->mmaps[i].mem); 1655 1656 trace_vfio_region_mmap(memory_region_name(®ion->mmaps[i].mem), 1657 region->mmaps[i].offset, 1658 region->mmaps[i].offset + 1659 region->mmaps[i].size - 1); 1660 } 1661 1662 return 0; 1663 } 1664 1665 void vfio_region_unmap(VFIORegion *region) 1666 { 1667 int i; 1668 1669 if (!region->mem) { 1670 return; 1671 } 1672 1673 for (i = 0; i < region->nr_mmaps; i++) { 1674 if (region->mmaps[i].mmap) { 1675 vfio_subregion_unmap(region, i); 1676 } 1677 } 1678 } 1679 1680 void vfio_region_exit(VFIORegion *region) 1681 { 1682 int i; 1683 1684 if (!region->mem) { 1685 return; 1686 } 1687 1688 for (i = 0; i < region->nr_mmaps; i++) { 1689 if (region->mmaps[i].mmap) { 1690 memory_region_del_subregion(region->mem, ®ion->mmaps[i].mem); 1691 } 1692 } 1693 1694 trace_vfio_region_exit(region->vbasedev->name, region->nr); 1695 } 1696 1697 void vfio_region_finalize(VFIORegion *region) 1698 { 1699 int i; 1700 1701 if (!region->mem) { 1702 return; 1703 } 1704 1705 for (i = 0; i < region->nr_mmaps; i++) { 1706 if (region->mmaps[i].mmap) { 1707 munmap(region->mmaps[i].mmap, region->mmaps[i].size); 1708 object_unparent(OBJECT(®ion->mmaps[i].mem)); 1709 } 1710 } 1711 1712 object_unparent(OBJECT(region->mem)); 1713 1714 g_free(region->mem); 1715 g_free(region->mmaps); 1716 1717 trace_vfio_region_finalize(region->vbasedev->name, region->nr); 1718 1719 region->mem = NULL; 1720 region->mmaps = NULL; 1721 region->nr_mmaps = 0; 1722 region->size = 0; 1723 region->flags = 0; 1724 region->nr = 0; 1725 } 1726 1727 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled) 1728 { 1729 int i; 1730 1731 if (!region->mem) { 1732 return; 1733 } 1734 1735 for (i = 0; i < region->nr_mmaps; i++) { 1736 if (region->mmaps[i].mmap) { 1737 memory_region_set_enabled(®ion->mmaps[i].mem, enabled); 1738 } 1739 } 1740 1741 trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem), 1742 enabled); 1743 } 1744 1745 void vfio_reset_handler(void *opaque) 1746 { 1747 VFIOGroup *group; 1748 VFIODevice *vbasedev; 1749 1750 QLIST_FOREACH(group, &vfio_group_list, next) { 1751 QLIST_FOREACH(vbasedev, &group->device_list, next) { 1752 if (vbasedev->dev->realized) { 1753 vbasedev->ops->vfio_compute_needs_reset(vbasedev); 1754 } 1755 } 1756 } 1757 1758 QLIST_FOREACH(group, &vfio_group_list, next) { 1759 QLIST_FOREACH(vbasedev, &group->device_list, next) { 1760 if (vbasedev->dev->realized && vbasedev->needs_reset) { 1761 vbasedev->ops->vfio_hot_reset_multi(vbasedev); 1762 } 1763 } 1764 } 1765 } 1766 1767 static void vfio_kvm_device_add_group(VFIOGroup *group) 1768 { 1769 #ifdef CONFIG_KVM 1770 struct kvm_device_attr attr = { 1771 .group = KVM_DEV_VFIO_GROUP, 1772 .attr = KVM_DEV_VFIO_GROUP_ADD, 1773 .addr = (uint64_t)(unsigned long)&group->fd, 1774 }; 1775 1776 if (!kvm_enabled()) { 1777 return; 1778 } 1779 1780 if (vfio_kvm_device_fd < 0) { 1781 struct kvm_create_device cd = { 1782 .type = KVM_DEV_TYPE_VFIO, 1783 }; 1784 1785 if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) { 1786 error_report("Failed to create KVM VFIO device: %m"); 1787 return; 1788 } 1789 1790 vfio_kvm_device_fd = cd.fd; 1791 } 1792 1793 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 1794 error_report("Failed to add group %d to KVM VFIO device: %m", 1795 group->groupid); 1796 } 1797 #endif 1798 } 1799 1800 static void vfio_kvm_device_del_group(VFIOGroup *group) 1801 { 1802 #ifdef CONFIG_KVM 1803 struct kvm_device_attr attr = { 1804 .group = KVM_DEV_VFIO_GROUP, 1805 .attr = KVM_DEV_VFIO_GROUP_DEL, 1806 .addr = (uint64_t)(unsigned long)&group->fd, 1807 }; 1808 1809 if (vfio_kvm_device_fd < 0) { 1810 return; 1811 } 1812 1813 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 1814 error_report("Failed to remove group %d from KVM VFIO device: %m", 1815 group->groupid); 1816 } 1817 #endif 1818 } 1819 1820 static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as) 1821 { 1822 VFIOAddressSpace *space; 1823 1824 QLIST_FOREACH(space, &vfio_address_spaces, list) { 1825 if (space->as == as) { 1826 return space; 1827 } 1828 } 1829 1830 /* No suitable VFIOAddressSpace, create a new one */ 1831 space = g_malloc0(sizeof(*space)); 1832 space->as = as; 1833 QLIST_INIT(&space->containers); 1834 1835 QLIST_INSERT_HEAD(&vfio_address_spaces, space, list); 1836 1837 return space; 1838 } 1839 1840 static void vfio_put_address_space(VFIOAddressSpace *space) 1841 { 1842 if (QLIST_EMPTY(&space->containers)) { 1843 QLIST_REMOVE(space, list); 1844 g_free(space); 1845 } 1846 } 1847 1848 /* 1849 * vfio_get_iommu_type - selects the richest iommu_type (v2 first) 1850 */ 1851 static int vfio_get_iommu_type(VFIOContainer *container, 1852 Error **errp) 1853 { 1854 int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU, 1855 VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU }; 1856 int i; 1857 1858 for (i = 0; i < ARRAY_SIZE(iommu_types); i++) { 1859 if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) { 1860 return iommu_types[i]; 1861 } 1862 } 1863 error_setg(errp, "No available IOMMU models"); 1864 return -EINVAL; 1865 } 1866 1867 static int vfio_init_container(VFIOContainer *container, int group_fd, 1868 Error **errp) 1869 { 1870 int iommu_type, ret; 1871 1872 iommu_type = vfio_get_iommu_type(container, errp); 1873 if (iommu_type < 0) { 1874 return iommu_type; 1875 } 1876 1877 ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd); 1878 if (ret) { 1879 error_setg_errno(errp, errno, "Failed to set group container"); 1880 return -errno; 1881 } 1882 1883 while (ioctl(container->fd, VFIO_SET_IOMMU, iommu_type)) { 1884 if (iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1885 /* 1886 * On sPAPR, despite the IOMMU subdriver always advertises v1 and 1887 * v2, the running platform may not support v2 and there is no 1888 * way to guess it until an IOMMU group gets added to the container. 1889 * So in case it fails with v2, try v1 as a fallback. 1890 */ 1891 iommu_type = VFIO_SPAPR_TCE_IOMMU; 1892 continue; 1893 } 1894 error_setg_errno(errp, errno, "Failed to set iommu for container"); 1895 return -errno; 1896 } 1897 1898 container->iommu_type = iommu_type; 1899 return 0; 1900 } 1901 1902 static int vfio_get_iommu_info(VFIOContainer *container, 1903 struct vfio_iommu_type1_info **info) 1904 { 1905 1906 size_t argsz = sizeof(struct vfio_iommu_type1_info); 1907 1908 *info = g_new0(struct vfio_iommu_type1_info, 1); 1909 again: 1910 (*info)->argsz = argsz; 1911 1912 if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) { 1913 g_free(*info); 1914 *info = NULL; 1915 return -errno; 1916 } 1917 1918 if (((*info)->argsz > argsz)) { 1919 argsz = (*info)->argsz; 1920 *info = g_realloc(*info, argsz); 1921 goto again; 1922 } 1923 1924 return 0; 1925 } 1926 1927 static struct vfio_info_cap_header * 1928 vfio_get_iommu_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) 1929 { 1930 struct vfio_info_cap_header *hdr; 1931 void *ptr = info; 1932 1933 if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { 1934 return NULL; 1935 } 1936 1937 for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) { 1938 if (hdr->id == id) { 1939 return hdr; 1940 } 1941 } 1942 1943 return NULL; 1944 } 1945 1946 static void vfio_get_iommu_info_migration(VFIOContainer *container, 1947 struct vfio_iommu_type1_info *info) 1948 { 1949 struct vfio_info_cap_header *hdr; 1950 struct vfio_iommu_type1_info_cap_migration *cap_mig; 1951 1952 hdr = vfio_get_iommu_info_cap(info, VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION); 1953 if (!hdr) { 1954 return; 1955 } 1956 1957 cap_mig = container_of(hdr, struct vfio_iommu_type1_info_cap_migration, 1958 header); 1959 1960 /* 1961 * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of 1962 * qemu_real_host_page_size to mark those dirty. 1963 */ 1964 if (cap_mig->pgsize_bitmap & qemu_real_host_page_size) { 1965 container->dirty_pages_supported = true; 1966 container->max_dirty_bitmap_size = cap_mig->max_dirty_bitmap_size; 1967 container->dirty_pgsizes = cap_mig->pgsize_bitmap; 1968 } 1969 } 1970 1971 static int vfio_connect_container(VFIOGroup *group, AddressSpace *as, 1972 Error **errp) 1973 { 1974 VFIOContainer *container; 1975 int ret, fd; 1976 VFIOAddressSpace *space; 1977 1978 space = vfio_get_address_space(as); 1979 1980 /* 1981 * VFIO is currently incompatible with discarding of RAM insofar as the 1982 * madvise to purge (zap) the page from QEMU's address space does not 1983 * interact with the memory API and therefore leaves stale virtual to 1984 * physical mappings in the IOMMU if the page was previously pinned. We 1985 * therefore set discarding broken for each group added to a container, 1986 * whether the container is used individually or shared. This provides 1987 * us with options to allow devices within a group to opt-in and allow 1988 * discarding, so long as it is done consistently for a group (for instance 1989 * if the device is an mdev device where it is known that the host vendor 1990 * driver will never pin pages outside of the working set of the guest 1991 * driver, which would thus not be discarding candidates). 1992 * 1993 * The first opportunity to induce pinning occurs here where we attempt to 1994 * attach the group to existing containers within the AddressSpace. If any 1995 * pages are already zapped from the virtual address space, such as from 1996 * previous discards, new pinning will cause valid mappings to be 1997 * re-established. Likewise, when the overall MemoryListener for a new 1998 * container is registered, a replay of mappings within the AddressSpace 1999 * will occur, re-establishing any previously zapped pages as well. 2000 * 2001 * Especially virtio-balloon is currently only prevented from discarding 2002 * new memory, it will not yet set ram_block_discard_set_required() and 2003 * therefore, neither stops us here or deals with the sudden memory 2004 * consumption of inflated memory. 2005 * 2006 * We do support discarding of memory coordinated via the RamDiscardManager 2007 * with some IOMMU types. vfio_ram_block_discard_disable() handles the 2008 * details once we know which type of IOMMU we are using. 2009 */ 2010 2011 QLIST_FOREACH(container, &space->containers, next) { 2012 if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) { 2013 ret = vfio_ram_block_discard_disable(container, true); 2014 if (ret) { 2015 error_setg_errno(errp, -ret, 2016 "Cannot set discarding of RAM broken"); 2017 if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, 2018 &container->fd)) { 2019 error_report("vfio: error disconnecting group %d from" 2020 " container", group->groupid); 2021 } 2022 return ret; 2023 } 2024 group->container = container; 2025 QLIST_INSERT_HEAD(&container->group_list, group, container_next); 2026 vfio_kvm_device_add_group(group); 2027 return 0; 2028 } 2029 } 2030 2031 fd = qemu_open_old("/dev/vfio/vfio", O_RDWR); 2032 if (fd < 0) { 2033 error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio"); 2034 ret = -errno; 2035 goto put_space_exit; 2036 } 2037 2038 ret = ioctl(fd, VFIO_GET_API_VERSION); 2039 if (ret != VFIO_API_VERSION) { 2040 error_setg(errp, "supported vfio version: %d, " 2041 "reported version: %d", VFIO_API_VERSION, ret); 2042 ret = -EINVAL; 2043 goto close_fd_exit; 2044 } 2045 2046 container = g_malloc0(sizeof(*container)); 2047 container->space = space; 2048 container->fd = fd; 2049 container->error = NULL; 2050 container->dirty_pages_supported = false; 2051 container->dma_max_mappings = 0; 2052 QLIST_INIT(&container->giommu_list); 2053 QLIST_INIT(&container->hostwin_list); 2054 QLIST_INIT(&container->vrdl_list); 2055 2056 ret = vfio_init_container(container, group->fd, errp); 2057 if (ret) { 2058 goto free_container_exit; 2059 } 2060 2061 ret = vfio_ram_block_discard_disable(container, true); 2062 if (ret) { 2063 error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken"); 2064 goto free_container_exit; 2065 } 2066 2067 switch (container->iommu_type) { 2068 case VFIO_TYPE1v2_IOMMU: 2069 case VFIO_TYPE1_IOMMU: 2070 { 2071 struct vfio_iommu_type1_info *info; 2072 2073 /* 2074 * FIXME: This assumes that a Type1 IOMMU can map any 64-bit 2075 * IOVA whatsoever. That's not actually true, but the current 2076 * kernel interface doesn't tell us what it can map, and the 2077 * existing Type1 IOMMUs generally support any IOVA we're 2078 * going to actually try in practice. 2079 */ 2080 ret = vfio_get_iommu_info(container, &info); 2081 2082 if (ret || !(info->flags & VFIO_IOMMU_INFO_PGSIZES)) { 2083 /* Assume 4k IOVA page size */ 2084 info->iova_pgsizes = 4096; 2085 } 2086 vfio_host_win_add(container, 0, (hwaddr)-1, info->iova_pgsizes); 2087 container->pgsizes = info->iova_pgsizes; 2088 2089 /* The default in the kernel ("dma_entry_limit") is 65535. */ 2090 container->dma_max_mappings = 65535; 2091 if (!ret) { 2092 vfio_get_info_dma_avail(info, &container->dma_max_mappings); 2093 vfio_get_iommu_info_migration(container, info); 2094 } 2095 g_free(info); 2096 break; 2097 } 2098 case VFIO_SPAPR_TCE_v2_IOMMU: 2099 case VFIO_SPAPR_TCE_IOMMU: 2100 { 2101 struct vfio_iommu_spapr_tce_info info; 2102 bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU; 2103 2104 /* 2105 * The host kernel code implementing VFIO_IOMMU_DISABLE is called 2106 * when container fd is closed so we do not call it explicitly 2107 * in this file. 2108 */ 2109 if (!v2) { 2110 ret = ioctl(fd, VFIO_IOMMU_ENABLE); 2111 if (ret) { 2112 error_setg_errno(errp, errno, "failed to enable container"); 2113 ret = -errno; 2114 goto enable_discards_exit; 2115 } 2116 } else { 2117 container->prereg_listener = vfio_prereg_listener; 2118 2119 memory_listener_register(&container->prereg_listener, 2120 &address_space_memory); 2121 if (container->error) { 2122 memory_listener_unregister(&container->prereg_listener); 2123 ret = -1; 2124 error_propagate_prepend(errp, container->error, 2125 "RAM memory listener initialization failed: "); 2126 goto enable_discards_exit; 2127 } 2128 } 2129 2130 info.argsz = sizeof(info); 2131 ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info); 2132 if (ret) { 2133 error_setg_errno(errp, errno, 2134 "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed"); 2135 ret = -errno; 2136 if (v2) { 2137 memory_listener_unregister(&container->prereg_listener); 2138 } 2139 goto enable_discards_exit; 2140 } 2141 2142 if (v2) { 2143 container->pgsizes = info.ddw.pgsizes; 2144 /* 2145 * There is a default window in just created container. 2146 * To make region_add/del simpler, we better remove this 2147 * window now and let those iommu_listener callbacks 2148 * create/remove them when needed. 2149 */ 2150 ret = vfio_spapr_remove_window(container, info.dma32_window_start); 2151 if (ret) { 2152 error_setg_errno(errp, -ret, 2153 "failed to remove existing window"); 2154 goto enable_discards_exit; 2155 } 2156 } else { 2157 /* The default table uses 4K pages */ 2158 container->pgsizes = 0x1000; 2159 vfio_host_win_add(container, info.dma32_window_start, 2160 info.dma32_window_start + 2161 info.dma32_window_size - 1, 2162 0x1000); 2163 } 2164 } 2165 } 2166 2167 vfio_kvm_device_add_group(group); 2168 2169 QLIST_INIT(&container->group_list); 2170 QLIST_INSERT_HEAD(&space->containers, container, next); 2171 2172 group->container = container; 2173 QLIST_INSERT_HEAD(&container->group_list, group, container_next); 2174 2175 container->listener = vfio_memory_listener; 2176 2177 memory_listener_register(&container->listener, container->space->as); 2178 2179 if (container->error) { 2180 ret = -1; 2181 error_propagate_prepend(errp, container->error, 2182 "memory listener initialization failed: "); 2183 goto listener_release_exit; 2184 } 2185 2186 container->initialized = true; 2187 2188 return 0; 2189 listener_release_exit: 2190 QLIST_REMOVE(group, container_next); 2191 QLIST_REMOVE(container, next); 2192 vfio_kvm_device_del_group(group); 2193 vfio_listener_release(container); 2194 2195 enable_discards_exit: 2196 vfio_ram_block_discard_disable(container, false); 2197 2198 free_container_exit: 2199 g_free(container); 2200 2201 close_fd_exit: 2202 close(fd); 2203 2204 put_space_exit: 2205 vfio_put_address_space(space); 2206 2207 return ret; 2208 } 2209 2210 static void vfio_disconnect_container(VFIOGroup *group) 2211 { 2212 VFIOContainer *container = group->container; 2213 2214 QLIST_REMOVE(group, container_next); 2215 group->container = NULL; 2216 2217 /* 2218 * Explicitly release the listener first before unset container, 2219 * since unset may destroy the backend container if it's the last 2220 * group. 2221 */ 2222 if (QLIST_EMPTY(&container->group_list)) { 2223 vfio_listener_release(container); 2224 } 2225 2226 if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) { 2227 error_report("vfio: error disconnecting group %d from container", 2228 group->groupid); 2229 } 2230 2231 if (QLIST_EMPTY(&container->group_list)) { 2232 VFIOAddressSpace *space = container->space; 2233 VFIOGuestIOMMU *giommu, *tmp; 2234 2235 QLIST_REMOVE(container, next); 2236 2237 QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) { 2238 memory_region_unregister_iommu_notifier( 2239 MEMORY_REGION(giommu->iommu), &giommu->n); 2240 QLIST_REMOVE(giommu, giommu_next); 2241 g_free(giommu); 2242 } 2243 2244 trace_vfio_disconnect_container(container->fd); 2245 close(container->fd); 2246 g_free(container); 2247 2248 vfio_put_address_space(space); 2249 } 2250 } 2251 2252 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp) 2253 { 2254 VFIOGroup *group; 2255 char path[32]; 2256 struct vfio_group_status status = { .argsz = sizeof(status) }; 2257 2258 QLIST_FOREACH(group, &vfio_group_list, next) { 2259 if (group->groupid == groupid) { 2260 /* Found it. Now is it already in the right context? */ 2261 if (group->container->space->as == as) { 2262 return group; 2263 } else { 2264 error_setg(errp, "group %d used in multiple address spaces", 2265 group->groupid); 2266 return NULL; 2267 } 2268 } 2269 } 2270 2271 group = g_malloc0(sizeof(*group)); 2272 2273 snprintf(path, sizeof(path), "/dev/vfio/%d", groupid); 2274 group->fd = qemu_open_old(path, O_RDWR); 2275 if (group->fd < 0) { 2276 error_setg_errno(errp, errno, "failed to open %s", path); 2277 goto free_group_exit; 2278 } 2279 2280 if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) { 2281 error_setg_errno(errp, errno, "failed to get group %d status", groupid); 2282 goto close_fd_exit; 2283 } 2284 2285 if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) { 2286 error_setg(errp, "group %d is not viable", groupid); 2287 error_append_hint(errp, 2288 "Please ensure all devices within the iommu_group " 2289 "are bound to their vfio bus driver.\n"); 2290 goto close_fd_exit; 2291 } 2292 2293 group->groupid = groupid; 2294 QLIST_INIT(&group->device_list); 2295 2296 if (vfio_connect_container(group, as, errp)) { 2297 error_prepend(errp, "failed to setup container for group %d: ", 2298 groupid); 2299 goto close_fd_exit; 2300 } 2301 2302 if (QLIST_EMPTY(&vfio_group_list)) { 2303 qemu_register_reset(vfio_reset_handler, NULL); 2304 } 2305 2306 QLIST_INSERT_HEAD(&vfio_group_list, group, next); 2307 2308 return group; 2309 2310 close_fd_exit: 2311 close(group->fd); 2312 2313 free_group_exit: 2314 g_free(group); 2315 2316 return NULL; 2317 } 2318 2319 void vfio_put_group(VFIOGroup *group) 2320 { 2321 if (!group || !QLIST_EMPTY(&group->device_list)) { 2322 return; 2323 } 2324 2325 if (!group->ram_block_discard_allowed) { 2326 vfio_ram_block_discard_disable(group->container, false); 2327 } 2328 vfio_kvm_device_del_group(group); 2329 vfio_disconnect_container(group); 2330 QLIST_REMOVE(group, next); 2331 trace_vfio_put_group(group->fd); 2332 close(group->fd); 2333 g_free(group); 2334 2335 if (QLIST_EMPTY(&vfio_group_list)) { 2336 qemu_unregister_reset(vfio_reset_handler, NULL); 2337 } 2338 } 2339 2340 int vfio_get_device(VFIOGroup *group, const char *name, 2341 VFIODevice *vbasedev, Error **errp) 2342 { 2343 struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) }; 2344 int ret, fd; 2345 2346 fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name); 2347 if (fd < 0) { 2348 error_setg_errno(errp, errno, "error getting device from group %d", 2349 group->groupid); 2350 error_append_hint(errp, 2351 "Verify all devices in group %d are bound to vfio-<bus> " 2352 "or pci-stub and not already in use\n", group->groupid); 2353 return fd; 2354 } 2355 2356 ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info); 2357 if (ret) { 2358 error_setg_errno(errp, errno, "error getting device info"); 2359 close(fd); 2360 return ret; 2361 } 2362 2363 /* 2364 * Set discarding of RAM as not broken for this group if the driver knows 2365 * the device operates compatibly with discarding. Setting must be 2366 * consistent per group, but since compatibility is really only possible 2367 * with mdev currently, we expect singleton groups. 2368 */ 2369 if (vbasedev->ram_block_discard_allowed != 2370 group->ram_block_discard_allowed) { 2371 if (!QLIST_EMPTY(&group->device_list)) { 2372 error_setg(errp, "Inconsistent setting of support for discarding " 2373 "RAM (e.g., balloon) within group"); 2374 close(fd); 2375 return -1; 2376 } 2377 2378 if (!group->ram_block_discard_allowed) { 2379 group->ram_block_discard_allowed = true; 2380 vfio_ram_block_discard_disable(group->container, false); 2381 } 2382 } 2383 2384 vbasedev->fd = fd; 2385 vbasedev->group = group; 2386 QLIST_INSERT_HEAD(&group->device_list, vbasedev, next); 2387 2388 vbasedev->num_irqs = dev_info.num_irqs; 2389 vbasedev->num_regions = dev_info.num_regions; 2390 vbasedev->flags = dev_info.flags; 2391 2392 trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions, 2393 dev_info.num_irqs); 2394 2395 vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET); 2396 return 0; 2397 } 2398 2399 void vfio_put_base_device(VFIODevice *vbasedev) 2400 { 2401 if (!vbasedev->group) { 2402 return; 2403 } 2404 QLIST_REMOVE(vbasedev, next); 2405 vbasedev->group = NULL; 2406 trace_vfio_put_base_device(vbasedev->fd); 2407 close(vbasedev->fd); 2408 } 2409 2410 int vfio_get_region_info(VFIODevice *vbasedev, int index, 2411 struct vfio_region_info **info) 2412 { 2413 size_t argsz = sizeof(struct vfio_region_info); 2414 2415 *info = g_malloc0(argsz); 2416 2417 (*info)->index = index; 2418 retry: 2419 (*info)->argsz = argsz; 2420 2421 if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) { 2422 g_free(*info); 2423 *info = NULL; 2424 return -errno; 2425 } 2426 2427 if ((*info)->argsz > argsz) { 2428 argsz = (*info)->argsz; 2429 *info = g_realloc(*info, argsz); 2430 2431 goto retry; 2432 } 2433 2434 return 0; 2435 } 2436 2437 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type, 2438 uint32_t subtype, struct vfio_region_info **info) 2439 { 2440 int i; 2441 2442 for (i = 0; i < vbasedev->num_regions; i++) { 2443 struct vfio_info_cap_header *hdr; 2444 struct vfio_region_info_cap_type *cap_type; 2445 2446 if (vfio_get_region_info(vbasedev, i, info)) { 2447 continue; 2448 } 2449 2450 hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE); 2451 if (!hdr) { 2452 g_free(*info); 2453 continue; 2454 } 2455 2456 cap_type = container_of(hdr, struct vfio_region_info_cap_type, header); 2457 2458 trace_vfio_get_dev_region(vbasedev->name, i, 2459 cap_type->type, cap_type->subtype); 2460 2461 if (cap_type->type == type && cap_type->subtype == subtype) { 2462 return 0; 2463 } 2464 2465 g_free(*info); 2466 } 2467 2468 *info = NULL; 2469 return -ENODEV; 2470 } 2471 2472 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type) 2473 { 2474 struct vfio_region_info *info = NULL; 2475 bool ret = false; 2476 2477 if (!vfio_get_region_info(vbasedev, region, &info)) { 2478 if (vfio_get_region_info_cap(info, cap_type)) { 2479 ret = true; 2480 } 2481 g_free(info); 2482 } 2483 2484 return ret; 2485 } 2486 2487 /* 2488 * Interfaces for IBM EEH (Enhanced Error Handling) 2489 */ 2490 static bool vfio_eeh_container_ok(VFIOContainer *container) 2491 { 2492 /* 2493 * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO 2494 * implementation is broken if there are multiple groups in a 2495 * container. The hardware works in units of Partitionable 2496 * Endpoints (== IOMMU groups) and the EEH operations naively 2497 * iterate across all groups in the container, without any logic 2498 * to make sure the groups have their state synchronized. For 2499 * certain operations (ENABLE) that might be ok, until an error 2500 * occurs, but for others (GET_STATE) it's clearly broken. 2501 */ 2502 2503 /* 2504 * XXX Once fixed kernels exist, test for them here 2505 */ 2506 2507 if (QLIST_EMPTY(&container->group_list)) { 2508 return false; 2509 } 2510 2511 if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) { 2512 return false; 2513 } 2514 2515 return true; 2516 } 2517 2518 static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op) 2519 { 2520 struct vfio_eeh_pe_op pe_op = { 2521 .argsz = sizeof(pe_op), 2522 .op = op, 2523 }; 2524 int ret; 2525 2526 if (!vfio_eeh_container_ok(container)) { 2527 error_report("vfio/eeh: EEH_PE_OP 0x%x: " 2528 "kernel requires a container with exactly one group", op); 2529 return -EPERM; 2530 } 2531 2532 ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op); 2533 if (ret < 0) { 2534 error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op); 2535 return -errno; 2536 } 2537 2538 return ret; 2539 } 2540 2541 static VFIOContainer *vfio_eeh_as_container(AddressSpace *as) 2542 { 2543 VFIOAddressSpace *space = vfio_get_address_space(as); 2544 VFIOContainer *container = NULL; 2545 2546 if (QLIST_EMPTY(&space->containers)) { 2547 /* No containers to act on */ 2548 goto out; 2549 } 2550 2551 container = QLIST_FIRST(&space->containers); 2552 2553 if (QLIST_NEXT(container, next)) { 2554 /* We don't yet have logic to synchronize EEH state across 2555 * multiple containers */ 2556 container = NULL; 2557 goto out; 2558 } 2559 2560 out: 2561 vfio_put_address_space(space); 2562 return container; 2563 } 2564 2565 bool vfio_eeh_as_ok(AddressSpace *as) 2566 { 2567 VFIOContainer *container = vfio_eeh_as_container(as); 2568 2569 return (container != NULL) && vfio_eeh_container_ok(container); 2570 } 2571 2572 int vfio_eeh_as_op(AddressSpace *as, uint32_t op) 2573 { 2574 VFIOContainer *container = vfio_eeh_as_container(as); 2575 2576 if (!container) { 2577 return -ENODEV; 2578 } 2579 return vfio_eeh_container_op(container, op); 2580 } 2581