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 g_free(hostwin); 555 return 0; 556 } 557 } 558 559 return -1; 560 } 561 562 static bool vfio_listener_skipped_section(MemoryRegionSection *section) 563 { 564 return (!memory_region_is_ram(section->mr) && 565 !memory_region_is_iommu(section->mr)) || 566 memory_region_is_protected(section->mr) || 567 /* 568 * Sizing an enabled 64-bit BAR can cause spurious mappings to 569 * addresses in the upper part of the 64-bit address space. These 570 * are never accessed by the CPU and beyond the address width of 571 * some IOMMU hardware. TODO: VFIO should tell us the IOMMU width. 572 */ 573 section->offset_within_address_space & (1ULL << 63); 574 } 575 576 /* Called with rcu_read_lock held. */ 577 static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr, 578 ram_addr_t *ram_addr, bool *read_only) 579 { 580 MemoryRegion *mr; 581 hwaddr xlat; 582 hwaddr len = iotlb->addr_mask + 1; 583 bool writable = iotlb->perm & IOMMU_WO; 584 585 /* 586 * The IOMMU TLB entry we have just covers translation through 587 * this IOMMU to its immediate target. We need to translate 588 * it the rest of the way through to memory. 589 */ 590 mr = address_space_translate(&address_space_memory, 591 iotlb->translated_addr, 592 &xlat, &len, writable, 593 MEMTXATTRS_UNSPECIFIED); 594 if (!memory_region_is_ram(mr)) { 595 error_report("iommu map to non memory area %"HWADDR_PRIx"", 596 xlat); 597 return false; 598 } else if (memory_region_has_ram_discard_manager(mr)) { 599 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(mr); 600 MemoryRegionSection tmp = { 601 .mr = mr, 602 .offset_within_region = xlat, 603 .size = int128_make64(len), 604 }; 605 606 /* 607 * Malicious VMs can map memory into the IOMMU, which is expected 608 * to remain discarded. vfio will pin all pages, populating memory. 609 * Disallow that. vmstate priorities make sure any RamDiscardManager 610 * were already restored before IOMMUs are restored. 611 */ 612 if (!ram_discard_manager_is_populated(rdm, &tmp)) { 613 error_report("iommu map to discarded memory (e.g., unplugged via" 614 " virtio-mem): %"HWADDR_PRIx"", 615 iotlb->translated_addr); 616 return false; 617 } 618 619 /* 620 * Malicious VMs might trigger discarding of IOMMU-mapped memory. The 621 * pages will remain pinned inside vfio until unmapped, resulting in a 622 * higher memory consumption than expected. If memory would get 623 * populated again later, there would be an inconsistency between pages 624 * pinned by vfio and pages seen by QEMU. This is the case until 625 * unmapped from the IOMMU (e.g., during device reset). 626 * 627 * With malicious guests, we really only care about pinning more memory 628 * than expected. RLIMIT_MEMLOCK set for the user/process can never be 629 * exceeded and can be used to mitigate this problem. 630 */ 631 warn_report_once("Using vfio with vIOMMUs and coordinated discarding of" 632 " RAM (e.g., virtio-mem) works, however, malicious" 633 " guests can trigger pinning of more memory than" 634 " intended via an IOMMU. It's possible to mitigate " 635 " by setting/adjusting RLIMIT_MEMLOCK."); 636 } 637 638 /* 639 * Translation truncates length to the IOMMU page size, 640 * check that it did not truncate too much. 641 */ 642 if (len & iotlb->addr_mask) { 643 error_report("iommu has granularity incompatible with target AS"); 644 return false; 645 } 646 647 if (vaddr) { 648 *vaddr = memory_region_get_ram_ptr(mr) + xlat; 649 } 650 651 if (ram_addr) { 652 *ram_addr = memory_region_get_ram_addr(mr) + xlat; 653 } 654 655 if (read_only) { 656 *read_only = !writable || mr->readonly; 657 } 658 659 return true; 660 } 661 662 static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 663 { 664 VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n); 665 VFIOContainer *container = giommu->container; 666 hwaddr iova = iotlb->iova + giommu->iommu_offset; 667 void *vaddr; 668 int ret; 669 670 trace_vfio_iommu_map_notify(iotlb->perm == IOMMU_NONE ? "UNMAP" : "MAP", 671 iova, iova + iotlb->addr_mask); 672 673 if (iotlb->target_as != &address_space_memory) { 674 error_report("Wrong target AS \"%s\", only system memory is allowed", 675 iotlb->target_as->name ? iotlb->target_as->name : "none"); 676 return; 677 } 678 679 rcu_read_lock(); 680 681 if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) { 682 bool read_only; 683 684 if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) { 685 goto out; 686 } 687 /* 688 * vaddr is only valid until rcu_read_unlock(). But after 689 * vfio_dma_map has set up the mapping the pages will be 690 * pinned by the kernel. This makes sure that the RAM backend 691 * of vaddr will always be there, even if the memory object is 692 * destroyed and its backing memory munmap-ed. 693 */ 694 ret = vfio_dma_map(container, iova, 695 iotlb->addr_mask + 1, vaddr, 696 read_only); 697 if (ret) { 698 error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", " 699 "0x%"HWADDR_PRIx", %p) = %d (%m)", 700 container, iova, 701 iotlb->addr_mask + 1, vaddr, ret); 702 } 703 } else { 704 ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb); 705 if (ret) { 706 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " 707 "0x%"HWADDR_PRIx") = %d (%m)", 708 container, iova, 709 iotlb->addr_mask + 1, ret); 710 } 711 } 712 out: 713 rcu_read_unlock(); 714 } 715 716 static void vfio_ram_discard_notify_discard(RamDiscardListener *rdl, 717 MemoryRegionSection *section) 718 { 719 VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, 720 listener); 721 const hwaddr size = int128_get64(section->size); 722 const hwaddr iova = section->offset_within_address_space; 723 int ret; 724 725 /* Unmap with a single call. */ 726 ret = vfio_dma_unmap(vrdl->container, iova, size , NULL); 727 if (ret) { 728 error_report("%s: vfio_dma_unmap() failed: %s", __func__, 729 strerror(-ret)); 730 } 731 } 732 733 static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl, 734 MemoryRegionSection *section) 735 { 736 VFIORamDiscardListener *vrdl = container_of(rdl, VFIORamDiscardListener, 737 listener); 738 const hwaddr end = section->offset_within_region + 739 int128_get64(section->size); 740 hwaddr start, next, iova; 741 void *vaddr; 742 int ret; 743 744 /* 745 * Map in (aligned within memory region) minimum granularity, so we can 746 * unmap in minimum granularity later. 747 */ 748 for (start = section->offset_within_region; start < end; start = next) { 749 next = ROUND_UP(start + 1, vrdl->granularity); 750 next = MIN(next, end); 751 752 iova = start - section->offset_within_region + 753 section->offset_within_address_space; 754 vaddr = memory_region_get_ram_ptr(section->mr) + start; 755 756 ret = vfio_dma_map(vrdl->container, iova, next - start, 757 vaddr, section->readonly); 758 if (ret) { 759 /* Rollback */ 760 vfio_ram_discard_notify_discard(rdl, section); 761 return ret; 762 } 763 } 764 return 0; 765 } 766 767 static void vfio_register_ram_discard_listener(VFIOContainer *container, 768 MemoryRegionSection *section) 769 { 770 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 771 VFIORamDiscardListener *vrdl; 772 773 /* Ignore some corner cases not relevant in practice. */ 774 g_assert(QEMU_IS_ALIGNED(section->offset_within_region, TARGET_PAGE_SIZE)); 775 g_assert(QEMU_IS_ALIGNED(section->offset_within_address_space, 776 TARGET_PAGE_SIZE)); 777 g_assert(QEMU_IS_ALIGNED(int128_get64(section->size), TARGET_PAGE_SIZE)); 778 779 vrdl = g_new0(VFIORamDiscardListener, 1); 780 vrdl->container = container; 781 vrdl->mr = section->mr; 782 vrdl->offset_within_address_space = section->offset_within_address_space; 783 vrdl->size = int128_get64(section->size); 784 vrdl->granularity = ram_discard_manager_get_min_granularity(rdm, 785 section->mr); 786 787 g_assert(vrdl->granularity && is_power_of_2(vrdl->granularity)); 788 g_assert(container->pgsizes && 789 vrdl->granularity >= 1ULL << ctz64(container->pgsizes)); 790 791 ram_discard_listener_init(&vrdl->listener, 792 vfio_ram_discard_notify_populate, 793 vfio_ram_discard_notify_discard, true); 794 ram_discard_manager_register_listener(rdm, &vrdl->listener, section); 795 QLIST_INSERT_HEAD(&container->vrdl_list, vrdl, next); 796 797 /* 798 * Sanity-check if we have a theoretically problematic setup where we could 799 * exceed the maximum number of possible DMA mappings over time. We assume 800 * that each mapped section in the same address space as a RamDiscardManager 801 * section consumes exactly one DMA mapping, with the exception of 802 * RamDiscardManager sections; i.e., we don't expect to have gIOMMU sections 803 * in the same address space as RamDiscardManager sections. 804 * 805 * We assume that each section in the address space consumes one memslot. 806 * We take the number of KVM memory slots as a best guess for the maximum 807 * number of sections in the address space we could have over time, 808 * also consuming DMA mappings. 809 */ 810 if (container->dma_max_mappings) { 811 unsigned int vrdl_count = 0, vrdl_mappings = 0, max_memslots = 512; 812 813 #ifdef CONFIG_KVM 814 if (kvm_enabled()) { 815 max_memslots = kvm_get_max_memslots(); 816 } 817 #endif 818 819 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 820 hwaddr start, end; 821 822 start = QEMU_ALIGN_DOWN(vrdl->offset_within_address_space, 823 vrdl->granularity); 824 end = ROUND_UP(vrdl->offset_within_address_space + vrdl->size, 825 vrdl->granularity); 826 vrdl_mappings += (end - start) / vrdl->granularity; 827 vrdl_count++; 828 } 829 830 if (vrdl_mappings + max_memslots - vrdl_count > 831 container->dma_max_mappings) { 832 warn_report("%s: possibly running out of DMA mappings. E.g., try" 833 " increasing the 'block-size' of virtio-mem devies." 834 " Maximum possible DMA mappings: %d, Maximum possible" 835 " memslots: %d", __func__, container->dma_max_mappings, 836 max_memslots); 837 } 838 } 839 } 840 841 static void vfio_unregister_ram_discard_listener(VFIOContainer *container, 842 MemoryRegionSection *section) 843 { 844 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 845 VFIORamDiscardListener *vrdl = NULL; 846 847 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 848 if (vrdl->mr == section->mr && 849 vrdl->offset_within_address_space == 850 section->offset_within_address_space) { 851 break; 852 } 853 } 854 855 if (!vrdl) { 856 hw_error("vfio: Trying to unregister missing RAM discard listener"); 857 } 858 859 ram_discard_manager_unregister_listener(rdm, &vrdl->listener); 860 QLIST_REMOVE(vrdl, next); 861 g_free(vrdl); 862 } 863 864 static void vfio_listener_region_add(MemoryListener *listener, 865 MemoryRegionSection *section) 866 { 867 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 868 hwaddr iova, end; 869 Int128 llend, llsize; 870 void *vaddr; 871 int ret; 872 VFIOHostDMAWindow *hostwin; 873 bool hostwin_found; 874 Error *err = NULL; 875 876 if (vfio_listener_skipped_section(section)) { 877 trace_vfio_listener_region_add_skip( 878 section->offset_within_address_space, 879 section->offset_within_address_space + 880 int128_get64(int128_sub(section->size, int128_one()))); 881 return; 882 } 883 884 if (unlikely((section->offset_within_address_space & 885 ~qemu_real_host_page_mask()) != 886 (section->offset_within_region & ~qemu_real_host_page_mask()))) { 887 error_report("%s received unaligned region", __func__); 888 return; 889 } 890 891 iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space); 892 llend = int128_make64(section->offset_within_address_space); 893 llend = int128_add(llend, section->size); 894 llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask())); 895 896 if (int128_ge(int128_make64(iova), llend)) { 897 if (memory_region_is_ram_device(section->mr)) { 898 trace_vfio_listener_region_add_no_dma_map( 899 memory_region_name(section->mr), 900 section->offset_within_address_space, 901 int128_getlo(section->size), 902 qemu_real_host_page_size()); 903 } 904 return; 905 } 906 end = int128_get64(int128_sub(llend, int128_one())); 907 908 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 909 hwaddr pgsize = 0; 910 911 /* For now intersections are not allowed, we may relax this later */ 912 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 913 if (ranges_overlap(hostwin->min_iova, 914 hostwin->max_iova - hostwin->min_iova + 1, 915 section->offset_within_address_space, 916 int128_get64(section->size))) { 917 error_setg(&err, 918 "region [0x%"PRIx64",0x%"PRIx64"] overlaps with existing" 919 "host DMA window [0x%"PRIx64",0x%"PRIx64"]", 920 section->offset_within_address_space, 921 section->offset_within_address_space + 922 int128_get64(section->size) - 1, 923 hostwin->min_iova, hostwin->max_iova); 924 goto fail; 925 } 926 } 927 928 ret = vfio_spapr_create_window(container, section, &pgsize); 929 if (ret) { 930 error_setg_errno(&err, -ret, "Failed to create SPAPR window"); 931 goto fail; 932 } 933 934 vfio_host_win_add(container, section->offset_within_address_space, 935 section->offset_within_address_space + 936 int128_get64(section->size) - 1, pgsize); 937 #ifdef CONFIG_KVM 938 if (kvm_enabled()) { 939 VFIOGroup *group; 940 IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr); 941 struct kvm_vfio_spapr_tce param; 942 struct kvm_device_attr attr = { 943 .group = KVM_DEV_VFIO_GROUP, 944 .attr = KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE, 945 .addr = (uint64_t)(unsigned long)¶m, 946 }; 947 948 if (!memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_SPAPR_TCE_FD, 949 ¶m.tablefd)) { 950 QLIST_FOREACH(group, &container->group_list, container_next) { 951 param.groupfd = group->fd; 952 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 953 error_report("vfio: failed to setup fd %d " 954 "for a group with fd %d: %s", 955 param.tablefd, param.groupfd, 956 strerror(errno)); 957 return; 958 } 959 trace_vfio_spapr_group_attach(param.groupfd, param.tablefd); 960 } 961 } 962 } 963 #endif 964 } 965 966 hostwin_found = false; 967 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 968 if (hostwin->min_iova <= iova && end <= hostwin->max_iova) { 969 hostwin_found = true; 970 break; 971 } 972 } 973 974 if (!hostwin_found) { 975 error_setg(&err, "Container %p can't map guest IOVA region" 976 " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, container, iova, end); 977 goto fail; 978 } 979 980 memory_region_ref(section->mr); 981 982 if (memory_region_is_iommu(section->mr)) { 983 VFIOGuestIOMMU *giommu; 984 IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr); 985 int iommu_idx; 986 987 trace_vfio_listener_region_add_iommu(iova, end); 988 /* 989 * FIXME: For VFIO iommu types which have KVM acceleration to 990 * avoid bouncing all map/unmaps through qemu this way, this 991 * would be the right place to wire that up (tell the KVM 992 * device emulation the VFIO iommu handles to use). 993 */ 994 giommu = g_malloc0(sizeof(*giommu)); 995 giommu->iommu = iommu_mr; 996 giommu->iommu_offset = section->offset_within_address_space - 997 section->offset_within_region; 998 giommu->container = container; 999 llend = int128_add(int128_make64(section->offset_within_region), 1000 section->size); 1001 llend = int128_sub(llend, int128_one()); 1002 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 1003 MEMTXATTRS_UNSPECIFIED); 1004 iommu_notifier_init(&giommu->n, vfio_iommu_map_notify, 1005 IOMMU_NOTIFIER_IOTLB_EVENTS, 1006 section->offset_within_region, 1007 int128_get64(llend), 1008 iommu_idx); 1009 1010 ret = memory_region_iommu_set_page_size_mask(giommu->iommu, 1011 container->pgsizes, 1012 &err); 1013 if (ret) { 1014 g_free(giommu); 1015 goto fail; 1016 } 1017 1018 ret = memory_region_register_iommu_notifier(section->mr, &giommu->n, 1019 &err); 1020 if (ret) { 1021 g_free(giommu); 1022 goto fail; 1023 } 1024 QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next); 1025 memory_region_iommu_replay(giommu->iommu, &giommu->n); 1026 1027 return; 1028 } 1029 1030 /* Here we assume that memory_region_is_ram(section->mr)==true */ 1031 1032 /* 1033 * For RAM memory regions with a RamDiscardManager, we only want to map the 1034 * actually populated parts - and update the mapping whenever we're notified 1035 * about changes. 1036 */ 1037 if (memory_region_has_ram_discard_manager(section->mr)) { 1038 vfio_register_ram_discard_listener(container, section); 1039 return; 1040 } 1041 1042 vaddr = memory_region_get_ram_ptr(section->mr) + 1043 section->offset_within_region + 1044 (iova - section->offset_within_address_space); 1045 1046 trace_vfio_listener_region_add_ram(iova, end, vaddr); 1047 1048 llsize = int128_sub(llend, int128_make64(iova)); 1049 1050 if (memory_region_is_ram_device(section->mr)) { 1051 hwaddr pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1; 1052 1053 if ((iova & pgmask) || (int128_get64(llsize) & pgmask)) { 1054 trace_vfio_listener_region_add_no_dma_map( 1055 memory_region_name(section->mr), 1056 section->offset_within_address_space, 1057 int128_getlo(section->size), 1058 pgmask + 1); 1059 return; 1060 } 1061 } 1062 1063 ret = vfio_dma_map(container, iova, int128_get64(llsize), 1064 vaddr, section->readonly); 1065 if (ret) { 1066 error_setg(&err, "vfio_dma_map(%p, 0x%"HWADDR_PRIx", " 1067 "0x%"HWADDR_PRIx", %p) = %d (%m)", 1068 container, iova, int128_get64(llsize), vaddr, ret); 1069 if (memory_region_is_ram_device(section->mr)) { 1070 /* Allow unexpected mappings not to be fatal for RAM devices */ 1071 error_report_err(err); 1072 return; 1073 } 1074 goto fail; 1075 } 1076 1077 return; 1078 1079 fail: 1080 if (memory_region_is_ram_device(section->mr)) { 1081 error_report("failed to vfio_dma_map. pci p2p may not work"); 1082 return; 1083 } 1084 /* 1085 * On the initfn path, store the first error in the container so we 1086 * can gracefully fail. Runtime, there's not much we can do other 1087 * than throw a hardware error. 1088 */ 1089 if (!container->initialized) { 1090 if (!container->error) { 1091 error_propagate_prepend(&container->error, err, 1092 "Region %s: ", 1093 memory_region_name(section->mr)); 1094 } else { 1095 error_free(err); 1096 } 1097 } else { 1098 error_report_err(err); 1099 hw_error("vfio: DMA mapping failed, unable to continue"); 1100 } 1101 } 1102 1103 static void vfio_listener_region_del(MemoryListener *listener, 1104 MemoryRegionSection *section) 1105 { 1106 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1107 hwaddr iova, end; 1108 Int128 llend, llsize; 1109 int ret; 1110 bool try_unmap = true; 1111 1112 if (vfio_listener_skipped_section(section)) { 1113 trace_vfio_listener_region_del_skip( 1114 section->offset_within_address_space, 1115 section->offset_within_address_space + 1116 int128_get64(int128_sub(section->size, int128_one()))); 1117 return; 1118 } 1119 1120 if (unlikely((section->offset_within_address_space & 1121 ~qemu_real_host_page_mask()) != 1122 (section->offset_within_region & ~qemu_real_host_page_mask()))) { 1123 error_report("%s received unaligned region", __func__); 1124 return; 1125 } 1126 1127 if (memory_region_is_iommu(section->mr)) { 1128 VFIOGuestIOMMU *giommu; 1129 1130 QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { 1131 if (MEMORY_REGION(giommu->iommu) == section->mr && 1132 giommu->n.start == section->offset_within_region) { 1133 memory_region_unregister_iommu_notifier(section->mr, 1134 &giommu->n); 1135 QLIST_REMOVE(giommu, giommu_next); 1136 g_free(giommu); 1137 break; 1138 } 1139 } 1140 1141 /* 1142 * FIXME: We assume the one big unmap below is adequate to 1143 * remove any individual page mappings in the IOMMU which 1144 * might have been copied into VFIO. This works for a page table 1145 * based IOMMU where a big unmap flattens a large range of IO-PTEs. 1146 * That may not be true for all IOMMU types. 1147 */ 1148 } 1149 1150 iova = REAL_HOST_PAGE_ALIGN(section->offset_within_address_space); 1151 llend = int128_make64(section->offset_within_address_space); 1152 llend = int128_add(llend, section->size); 1153 llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask())); 1154 1155 if (int128_ge(int128_make64(iova), llend)) { 1156 return; 1157 } 1158 end = int128_get64(int128_sub(llend, int128_one())); 1159 1160 llsize = int128_sub(llend, int128_make64(iova)); 1161 1162 trace_vfio_listener_region_del(iova, end); 1163 1164 if (memory_region_is_ram_device(section->mr)) { 1165 hwaddr pgmask; 1166 VFIOHostDMAWindow *hostwin; 1167 bool hostwin_found = false; 1168 1169 QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) { 1170 if (hostwin->min_iova <= iova && end <= hostwin->max_iova) { 1171 hostwin_found = true; 1172 break; 1173 } 1174 } 1175 assert(hostwin_found); /* or region_add() would have failed */ 1176 1177 pgmask = (1ULL << ctz64(hostwin->iova_pgsizes)) - 1; 1178 try_unmap = !((iova & pgmask) || (int128_get64(llsize) & pgmask)); 1179 } else if (memory_region_has_ram_discard_manager(section->mr)) { 1180 vfio_unregister_ram_discard_listener(container, section); 1181 /* Unregistering will trigger an unmap. */ 1182 try_unmap = false; 1183 } 1184 1185 if (try_unmap) { 1186 if (int128_eq(llsize, int128_2_64())) { 1187 /* The unmap ioctl doesn't accept a full 64-bit span. */ 1188 llsize = int128_rshift(llsize, 1); 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 iova += int128_get64(llsize); 1196 } 1197 ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL); 1198 if (ret) { 1199 error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " 1200 "0x%"HWADDR_PRIx") = %d (%m)", 1201 container, iova, int128_get64(llsize), ret); 1202 } 1203 } 1204 1205 memory_region_unref(section->mr); 1206 1207 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1208 vfio_spapr_remove_window(container, 1209 section->offset_within_address_space); 1210 if (vfio_host_win_del(container, 1211 section->offset_within_address_space, 1212 section->offset_within_address_space + 1213 int128_get64(section->size) - 1) < 0) { 1214 hw_error("%s: Cannot delete missing window at %"HWADDR_PRIx, 1215 __func__, section->offset_within_address_space); 1216 } 1217 } 1218 } 1219 1220 static void vfio_set_dirty_page_tracking(VFIOContainer *container, bool start) 1221 { 1222 int ret; 1223 struct vfio_iommu_type1_dirty_bitmap dirty = { 1224 .argsz = sizeof(dirty), 1225 }; 1226 1227 if (start) { 1228 dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_START; 1229 } else { 1230 dirty.flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP; 1231 } 1232 1233 ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, &dirty); 1234 if (ret) { 1235 error_report("Failed to set dirty tracking flag 0x%x errno: %d", 1236 dirty.flags, errno); 1237 } 1238 } 1239 1240 static void vfio_listener_log_global_start(MemoryListener *listener) 1241 { 1242 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1243 1244 vfio_set_dirty_page_tracking(container, true); 1245 } 1246 1247 static void vfio_listener_log_global_stop(MemoryListener *listener) 1248 { 1249 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1250 1251 vfio_set_dirty_page_tracking(container, false); 1252 } 1253 1254 static int vfio_get_dirty_bitmap(VFIOContainer *container, uint64_t iova, 1255 uint64_t size, ram_addr_t ram_addr) 1256 { 1257 struct vfio_iommu_type1_dirty_bitmap *dbitmap; 1258 struct vfio_iommu_type1_dirty_bitmap_get *range; 1259 uint64_t pages; 1260 int ret; 1261 1262 dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range)); 1263 1264 dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range); 1265 dbitmap->flags = VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP; 1266 range = (struct vfio_iommu_type1_dirty_bitmap_get *)&dbitmap->data; 1267 range->iova = iova; 1268 range->size = size; 1269 1270 /* 1271 * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of 1272 * qemu_real_host_page_size to mark those dirty. Hence set bitmap's pgsize 1273 * to qemu_real_host_page_size. 1274 */ 1275 range->bitmap.pgsize = qemu_real_host_page_size(); 1276 1277 pages = REAL_HOST_PAGE_ALIGN(range->size) / qemu_real_host_page_size(); 1278 range->bitmap.size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) / 1279 BITS_PER_BYTE; 1280 range->bitmap.data = g_try_malloc0(range->bitmap.size); 1281 if (!range->bitmap.data) { 1282 ret = -ENOMEM; 1283 goto err_out; 1284 } 1285 1286 ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap); 1287 if (ret) { 1288 error_report("Failed to get dirty bitmap for iova: 0x%"PRIx64 1289 " size: 0x%"PRIx64" err: %d", (uint64_t)range->iova, 1290 (uint64_t)range->size, errno); 1291 goto err_out; 1292 } 1293 1294 cpu_physical_memory_set_dirty_lebitmap((unsigned long *)range->bitmap.data, 1295 ram_addr, pages); 1296 1297 trace_vfio_get_dirty_bitmap(container->fd, range->iova, range->size, 1298 range->bitmap.size, ram_addr); 1299 err_out: 1300 g_free(range->bitmap.data); 1301 g_free(dbitmap); 1302 1303 return ret; 1304 } 1305 1306 typedef struct { 1307 IOMMUNotifier n; 1308 VFIOGuestIOMMU *giommu; 1309 } vfio_giommu_dirty_notifier; 1310 1311 static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 1312 { 1313 vfio_giommu_dirty_notifier *gdn = container_of(n, 1314 vfio_giommu_dirty_notifier, n); 1315 VFIOGuestIOMMU *giommu = gdn->giommu; 1316 VFIOContainer *container = giommu->container; 1317 hwaddr iova = iotlb->iova + giommu->iommu_offset; 1318 ram_addr_t translated_addr; 1319 1320 trace_vfio_iommu_map_dirty_notify(iova, iova + iotlb->addr_mask); 1321 1322 if (iotlb->target_as != &address_space_memory) { 1323 error_report("Wrong target AS \"%s\", only system memory is allowed", 1324 iotlb->target_as->name ? iotlb->target_as->name : "none"); 1325 return; 1326 } 1327 1328 rcu_read_lock(); 1329 if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) { 1330 int ret; 1331 1332 ret = vfio_get_dirty_bitmap(container, iova, iotlb->addr_mask + 1, 1333 translated_addr); 1334 if (ret) { 1335 error_report("vfio_iommu_map_dirty_notify(%p, 0x%"HWADDR_PRIx", " 1336 "0x%"HWADDR_PRIx") = %d (%m)", 1337 container, iova, 1338 iotlb->addr_mask + 1, ret); 1339 } 1340 } 1341 rcu_read_unlock(); 1342 } 1343 1344 static int vfio_ram_discard_get_dirty_bitmap(MemoryRegionSection *section, 1345 void *opaque) 1346 { 1347 const hwaddr size = int128_get64(section->size); 1348 const hwaddr iova = section->offset_within_address_space; 1349 const ram_addr_t ram_addr = memory_region_get_ram_addr(section->mr) + 1350 section->offset_within_region; 1351 VFIORamDiscardListener *vrdl = opaque; 1352 1353 /* 1354 * Sync the whole mapped region (spanning multiple individual mappings) 1355 * in one go. 1356 */ 1357 return vfio_get_dirty_bitmap(vrdl->container, iova, size, ram_addr); 1358 } 1359 1360 static int vfio_sync_ram_discard_listener_dirty_bitmap(VFIOContainer *container, 1361 MemoryRegionSection *section) 1362 { 1363 RamDiscardManager *rdm = memory_region_get_ram_discard_manager(section->mr); 1364 VFIORamDiscardListener *vrdl = NULL; 1365 1366 QLIST_FOREACH(vrdl, &container->vrdl_list, next) { 1367 if (vrdl->mr == section->mr && 1368 vrdl->offset_within_address_space == 1369 section->offset_within_address_space) { 1370 break; 1371 } 1372 } 1373 1374 if (!vrdl) { 1375 hw_error("vfio: Trying to sync missing RAM discard listener"); 1376 } 1377 1378 /* 1379 * We only want/can synchronize the bitmap for actually mapped parts - 1380 * which correspond to populated parts. Replay all populated parts. 1381 */ 1382 return ram_discard_manager_replay_populated(rdm, section, 1383 vfio_ram_discard_get_dirty_bitmap, 1384 &vrdl); 1385 } 1386 1387 static int vfio_sync_dirty_bitmap(VFIOContainer *container, 1388 MemoryRegionSection *section) 1389 { 1390 ram_addr_t ram_addr; 1391 1392 if (memory_region_is_iommu(section->mr)) { 1393 VFIOGuestIOMMU *giommu; 1394 1395 QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { 1396 if (MEMORY_REGION(giommu->iommu) == section->mr && 1397 giommu->n.start == section->offset_within_region) { 1398 Int128 llend; 1399 vfio_giommu_dirty_notifier gdn = { .giommu = giommu }; 1400 int idx = memory_region_iommu_attrs_to_index(giommu->iommu, 1401 MEMTXATTRS_UNSPECIFIED); 1402 1403 llend = int128_add(int128_make64(section->offset_within_region), 1404 section->size); 1405 llend = int128_sub(llend, int128_one()); 1406 1407 iommu_notifier_init(&gdn.n, 1408 vfio_iommu_map_dirty_notify, 1409 IOMMU_NOTIFIER_MAP, 1410 section->offset_within_region, 1411 int128_get64(llend), 1412 idx); 1413 memory_region_iommu_replay(giommu->iommu, &gdn.n); 1414 break; 1415 } 1416 } 1417 return 0; 1418 } else if (memory_region_has_ram_discard_manager(section->mr)) { 1419 return vfio_sync_ram_discard_listener_dirty_bitmap(container, section); 1420 } 1421 1422 ram_addr = memory_region_get_ram_addr(section->mr) + 1423 section->offset_within_region; 1424 1425 return vfio_get_dirty_bitmap(container, 1426 REAL_HOST_PAGE_ALIGN(section->offset_within_address_space), 1427 int128_get64(section->size), ram_addr); 1428 } 1429 1430 static void vfio_listener_log_sync(MemoryListener *listener, 1431 MemoryRegionSection *section) 1432 { 1433 VFIOContainer *container = container_of(listener, VFIOContainer, listener); 1434 1435 if (vfio_listener_skipped_section(section) || 1436 !container->dirty_pages_supported) { 1437 return; 1438 } 1439 1440 if (vfio_devices_all_dirty_tracking(container)) { 1441 vfio_sync_dirty_bitmap(container, section); 1442 } 1443 } 1444 1445 static const MemoryListener vfio_memory_listener = { 1446 .name = "vfio", 1447 .region_add = vfio_listener_region_add, 1448 .region_del = vfio_listener_region_del, 1449 .log_global_start = vfio_listener_log_global_start, 1450 .log_global_stop = vfio_listener_log_global_stop, 1451 .log_sync = vfio_listener_log_sync, 1452 }; 1453 1454 static void vfio_listener_release(VFIOContainer *container) 1455 { 1456 memory_listener_unregister(&container->listener); 1457 if (container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1458 memory_listener_unregister(&container->prereg_listener); 1459 } 1460 } 1461 1462 static struct vfio_info_cap_header * 1463 vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id) 1464 { 1465 struct vfio_info_cap_header *hdr; 1466 1467 for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) { 1468 if (hdr->id == id) { 1469 return hdr; 1470 } 1471 } 1472 1473 return NULL; 1474 } 1475 1476 struct vfio_info_cap_header * 1477 vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id) 1478 { 1479 if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) { 1480 return NULL; 1481 } 1482 1483 return vfio_get_cap((void *)info, info->cap_offset, id); 1484 } 1485 1486 static struct vfio_info_cap_header * 1487 vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) 1488 { 1489 if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { 1490 return NULL; 1491 } 1492 1493 return vfio_get_cap((void *)info, info->cap_offset, id); 1494 } 1495 1496 struct vfio_info_cap_header * 1497 vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id) 1498 { 1499 if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) { 1500 return NULL; 1501 } 1502 1503 return vfio_get_cap((void *)info, info->cap_offset, id); 1504 } 1505 1506 bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info, 1507 unsigned int *avail) 1508 { 1509 struct vfio_info_cap_header *hdr; 1510 struct vfio_iommu_type1_info_dma_avail *cap; 1511 1512 /* If the capability cannot be found, assume no DMA limiting */ 1513 hdr = vfio_get_iommu_type1_info_cap(info, 1514 VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL); 1515 if (hdr == NULL) { 1516 return false; 1517 } 1518 1519 if (avail != NULL) { 1520 cap = (void *) hdr; 1521 *avail = cap->avail; 1522 } 1523 1524 return true; 1525 } 1526 1527 static int vfio_setup_region_sparse_mmaps(VFIORegion *region, 1528 struct vfio_region_info *info) 1529 { 1530 struct vfio_info_cap_header *hdr; 1531 struct vfio_region_info_cap_sparse_mmap *sparse; 1532 int i, j; 1533 1534 hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP); 1535 if (!hdr) { 1536 return -ENODEV; 1537 } 1538 1539 sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header); 1540 1541 trace_vfio_region_sparse_mmap_header(region->vbasedev->name, 1542 region->nr, sparse->nr_areas); 1543 1544 region->mmaps = g_new0(VFIOMmap, sparse->nr_areas); 1545 1546 for (i = 0, j = 0; i < sparse->nr_areas; i++) { 1547 trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset, 1548 sparse->areas[i].offset + 1549 sparse->areas[i].size); 1550 1551 if (sparse->areas[i].size) { 1552 region->mmaps[j].offset = sparse->areas[i].offset; 1553 region->mmaps[j].size = sparse->areas[i].size; 1554 j++; 1555 } 1556 } 1557 1558 region->nr_mmaps = j; 1559 region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap)); 1560 1561 return 0; 1562 } 1563 1564 int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region, 1565 int index, const char *name) 1566 { 1567 struct vfio_region_info *info; 1568 int ret; 1569 1570 ret = vfio_get_region_info(vbasedev, index, &info); 1571 if (ret) { 1572 return ret; 1573 } 1574 1575 region->vbasedev = vbasedev; 1576 region->flags = info->flags; 1577 region->size = info->size; 1578 region->fd_offset = info->offset; 1579 region->nr = index; 1580 1581 if (region->size) { 1582 region->mem = g_new0(MemoryRegion, 1); 1583 memory_region_init_io(region->mem, obj, &vfio_region_ops, 1584 region, name, region->size); 1585 1586 if (!vbasedev->no_mmap && 1587 region->flags & VFIO_REGION_INFO_FLAG_MMAP) { 1588 1589 ret = vfio_setup_region_sparse_mmaps(region, info); 1590 1591 if (ret) { 1592 region->nr_mmaps = 1; 1593 region->mmaps = g_new0(VFIOMmap, region->nr_mmaps); 1594 region->mmaps[0].offset = 0; 1595 region->mmaps[0].size = region->size; 1596 } 1597 } 1598 } 1599 1600 g_free(info); 1601 1602 trace_vfio_region_setup(vbasedev->name, index, name, 1603 region->flags, region->fd_offset, region->size); 1604 return 0; 1605 } 1606 1607 static void vfio_subregion_unmap(VFIORegion *region, int index) 1608 { 1609 trace_vfio_region_unmap(memory_region_name(®ion->mmaps[index].mem), 1610 region->mmaps[index].offset, 1611 region->mmaps[index].offset + 1612 region->mmaps[index].size - 1); 1613 memory_region_del_subregion(region->mem, ®ion->mmaps[index].mem); 1614 munmap(region->mmaps[index].mmap, region->mmaps[index].size); 1615 object_unparent(OBJECT(®ion->mmaps[index].mem)); 1616 region->mmaps[index].mmap = NULL; 1617 } 1618 1619 int vfio_region_mmap(VFIORegion *region) 1620 { 1621 int i, prot = 0; 1622 char *name; 1623 1624 if (!region->mem) { 1625 return 0; 1626 } 1627 1628 prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0; 1629 prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0; 1630 1631 for (i = 0; i < region->nr_mmaps; i++) { 1632 region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot, 1633 MAP_SHARED, region->vbasedev->fd, 1634 region->fd_offset + 1635 region->mmaps[i].offset); 1636 if (region->mmaps[i].mmap == MAP_FAILED) { 1637 int ret = -errno; 1638 1639 trace_vfio_region_mmap_fault(memory_region_name(region->mem), i, 1640 region->fd_offset + 1641 region->mmaps[i].offset, 1642 region->fd_offset + 1643 region->mmaps[i].offset + 1644 region->mmaps[i].size - 1, ret); 1645 1646 region->mmaps[i].mmap = NULL; 1647 1648 for (i--; i >= 0; i--) { 1649 vfio_subregion_unmap(region, i); 1650 } 1651 1652 return ret; 1653 } 1654 1655 name = g_strdup_printf("%s mmaps[%d]", 1656 memory_region_name(region->mem), i); 1657 memory_region_init_ram_device_ptr(®ion->mmaps[i].mem, 1658 memory_region_owner(region->mem), 1659 name, region->mmaps[i].size, 1660 region->mmaps[i].mmap); 1661 g_free(name); 1662 memory_region_add_subregion(region->mem, region->mmaps[i].offset, 1663 ®ion->mmaps[i].mem); 1664 1665 trace_vfio_region_mmap(memory_region_name(®ion->mmaps[i].mem), 1666 region->mmaps[i].offset, 1667 region->mmaps[i].offset + 1668 region->mmaps[i].size - 1); 1669 } 1670 1671 return 0; 1672 } 1673 1674 void vfio_region_unmap(VFIORegion *region) 1675 { 1676 int i; 1677 1678 if (!region->mem) { 1679 return; 1680 } 1681 1682 for (i = 0; i < region->nr_mmaps; i++) { 1683 if (region->mmaps[i].mmap) { 1684 vfio_subregion_unmap(region, i); 1685 } 1686 } 1687 } 1688 1689 void vfio_region_exit(VFIORegion *region) 1690 { 1691 int i; 1692 1693 if (!region->mem) { 1694 return; 1695 } 1696 1697 for (i = 0; i < region->nr_mmaps; i++) { 1698 if (region->mmaps[i].mmap) { 1699 memory_region_del_subregion(region->mem, ®ion->mmaps[i].mem); 1700 } 1701 } 1702 1703 trace_vfio_region_exit(region->vbasedev->name, region->nr); 1704 } 1705 1706 void vfio_region_finalize(VFIORegion *region) 1707 { 1708 int i; 1709 1710 if (!region->mem) { 1711 return; 1712 } 1713 1714 for (i = 0; i < region->nr_mmaps; i++) { 1715 if (region->mmaps[i].mmap) { 1716 munmap(region->mmaps[i].mmap, region->mmaps[i].size); 1717 object_unparent(OBJECT(®ion->mmaps[i].mem)); 1718 } 1719 } 1720 1721 object_unparent(OBJECT(region->mem)); 1722 1723 g_free(region->mem); 1724 g_free(region->mmaps); 1725 1726 trace_vfio_region_finalize(region->vbasedev->name, region->nr); 1727 1728 region->mem = NULL; 1729 region->mmaps = NULL; 1730 region->nr_mmaps = 0; 1731 region->size = 0; 1732 region->flags = 0; 1733 region->nr = 0; 1734 } 1735 1736 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled) 1737 { 1738 int i; 1739 1740 if (!region->mem) { 1741 return; 1742 } 1743 1744 for (i = 0; i < region->nr_mmaps; i++) { 1745 if (region->mmaps[i].mmap) { 1746 memory_region_set_enabled(®ion->mmaps[i].mem, enabled); 1747 } 1748 } 1749 1750 trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem), 1751 enabled); 1752 } 1753 1754 void vfio_reset_handler(void *opaque) 1755 { 1756 VFIOGroup *group; 1757 VFIODevice *vbasedev; 1758 1759 QLIST_FOREACH(group, &vfio_group_list, next) { 1760 QLIST_FOREACH(vbasedev, &group->device_list, next) { 1761 if (vbasedev->dev->realized) { 1762 vbasedev->ops->vfio_compute_needs_reset(vbasedev); 1763 } 1764 } 1765 } 1766 1767 QLIST_FOREACH(group, &vfio_group_list, next) { 1768 QLIST_FOREACH(vbasedev, &group->device_list, next) { 1769 if (vbasedev->dev->realized && vbasedev->needs_reset) { 1770 vbasedev->ops->vfio_hot_reset_multi(vbasedev); 1771 } 1772 } 1773 } 1774 } 1775 1776 static void vfio_kvm_device_add_group(VFIOGroup *group) 1777 { 1778 #ifdef CONFIG_KVM 1779 struct kvm_device_attr attr = { 1780 .group = KVM_DEV_VFIO_GROUP, 1781 .attr = KVM_DEV_VFIO_GROUP_ADD, 1782 .addr = (uint64_t)(unsigned long)&group->fd, 1783 }; 1784 1785 if (!kvm_enabled()) { 1786 return; 1787 } 1788 1789 if (vfio_kvm_device_fd < 0) { 1790 struct kvm_create_device cd = { 1791 .type = KVM_DEV_TYPE_VFIO, 1792 }; 1793 1794 if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) { 1795 error_report("Failed to create KVM VFIO device: %m"); 1796 return; 1797 } 1798 1799 vfio_kvm_device_fd = cd.fd; 1800 } 1801 1802 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 1803 error_report("Failed to add group %d to KVM VFIO device: %m", 1804 group->groupid); 1805 } 1806 #endif 1807 } 1808 1809 static void vfio_kvm_device_del_group(VFIOGroup *group) 1810 { 1811 #ifdef CONFIG_KVM 1812 struct kvm_device_attr attr = { 1813 .group = KVM_DEV_VFIO_GROUP, 1814 .attr = KVM_DEV_VFIO_GROUP_DEL, 1815 .addr = (uint64_t)(unsigned long)&group->fd, 1816 }; 1817 1818 if (vfio_kvm_device_fd < 0) { 1819 return; 1820 } 1821 1822 if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) { 1823 error_report("Failed to remove group %d from KVM VFIO device: %m", 1824 group->groupid); 1825 } 1826 #endif 1827 } 1828 1829 static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as) 1830 { 1831 VFIOAddressSpace *space; 1832 1833 QLIST_FOREACH(space, &vfio_address_spaces, list) { 1834 if (space->as == as) { 1835 return space; 1836 } 1837 } 1838 1839 /* No suitable VFIOAddressSpace, create a new one */ 1840 space = g_malloc0(sizeof(*space)); 1841 space->as = as; 1842 QLIST_INIT(&space->containers); 1843 1844 QLIST_INSERT_HEAD(&vfio_address_spaces, space, list); 1845 1846 return space; 1847 } 1848 1849 static void vfio_put_address_space(VFIOAddressSpace *space) 1850 { 1851 if (QLIST_EMPTY(&space->containers)) { 1852 QLIST_REMOVE(space, list); 1853 g_free(space); 1854 } 1855 } 1856 1857 /* 1858 * vfio_get_iommu_type - selects the richest iommu_type (v2 first) 1859 */ 1860 static int vfio_get_iommu_type(VFIOContainer *container, 1861 Error **errp) 1862 { 1863 int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU, 1864 VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU }; 1865 int i; 1866 1867 for (i = 0; i < ARRAY_SIZE(iommu_types); i++) { 1868 if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) { 1869 return iommu_types[i]; 1870 } 1871 } 1872 error_setg(errp, "No available IOMMU models"); 1873 return -EINVAL; 1874 } 1875 1876 static int vfio_init_container(VFIOContainer *container, int group_fd, 1877 Error **errp) 1878 { 1879 int iommu_type, ret; 1880 1881 iommu_type = vfio_get_iommu_type(container, errp); 1882 if (iommu_type < 0) { 1883 return iommu_type; 1884 } 1885 1886 ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd); 1887 if (ret) { 1888 error_setg_errno(errp, errno, "Failed to set group container"); 1889 return -errno; 1890 } 1891 1892 while (ioctl(container->fd, VFIO_SET_IOMMU, iommu_type)) { 1893 if (iommu_type == VFIO_SPAPR_TCE_v2_IOMMU) { 1894 /* 1895 * On sPAPR, despite the IOMMU subdriver always advertises v1 and 1896 * v2, the running platform may not support v2 and there is no 1897 * way to guess it until an IOMMU group gets added to the container. 1898 * So in case it fails with v2, try v1 as a fallback. 1899 */ 1900 iommu_type = VFIO_SPAPR_TCE_IOMMU; 1901 continue; 1902 } 1903 error_setg_errno(errp, errno, "Failed to set iommu for container"); 1904 return -errno; 1905 } 1906 1907 container->iommu_type = iommu_type; 1908 return 0; 1909 } 1910 1911 static int vfio_get_iommu_info(VFIOContainer *container, 1912 struct vfio_iommu_type1_info **info) 1913 { 1914 1915 size_t argsz = sizeof(struct vfio_iommu_type1_info); 1916 1917 *info = g_new0(struct vfio_iommu_type1_info, 1); 1918 again: 1919 (*info)->argsz = argsz; 1920 1921 if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) { 1922 g_free(*info); 1923 *info = NULL; 1924 return -errno; 1925 } 1926 1927 if (((*info)->argsz > argsz)) { 1928 argsz = (*info)->argsz; 1929 *info = g_realloc(*info, argsz); 1930 goto again; 1931 } 1932 1933 return 0; 1934 } 1935 1936 static struct vfio_info_cap_header * 1937 vfio_get_iommu_info_cap(struct vfio_iommu_type1_info *info, uint16_t id) 1938 { 1939 struct vfio_info_cap_header *hdr; 1940 void *ptr = info; 1941 1942 if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) { 1943 return NULL; 1944 } 1945 1946 for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) { 1947 if (hdr->id == id) { 1948 return hdr; 1949 } 1950 } 1951 1952 return NULL; 1953 } 1954 1955 static void vfio_get_iommu_info_migration(VFIOContainer *container, 1956 struct vfio_iommu_type1_info *info) 1957 { 1958 struct vfio_info_cap_header *hdr; 1959 struct vfio_iommu_type1_info_cap_migration *cap_mig; 1960 1961 hdr = vfio_get_iommu_info_cap(info, VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION); 1962 if (!hdr) { 1963 return; 1964 } 1965 1966 cap_mig = container_of(hdr, struct vfio_iommu_type1_info_cap_migration, 1967 header); 1968 1969 /* 1970 * cpu_physical_memory_set_dirty_lebitmap() supports pages in bitmap of 1971 * qemu_real_host_page_size to mark those dirty. 1972 */ 1973 if (cap_mig->pgsize_bitmap & qemu_real_host_page_size()) { 1974 container->dirty_pages_supported = true; 1975 container->max_dirty_bitmap_size = cap_mig->max_dirty_bitmap_size; 1976 container->dirty_pgsizes = cap_mig->pgsize_bitmap; 1977 } 1978 } 1979 1980 static int vfio_connect_container(VFIOGroup *group, AddressSpace *as, 1981 Error **errp) 1982 { 1983 VFIOContainer *container; 1984 int ret, fd; 1985 VFIOAddressSpace *space; 1986 1987 space = vfio_get_address_space(as); 1988 1989 /* 1990 * VFIO is currently incompatible with discarding of RAM insofar as the 1991 * madvise to purge (zap) the page from QEMU's address space does not 1992 * interact with the memory API and therefore leaves stale virtual to 1993 * physical mappings in the IOMMU if the page was previously pinned. We 1994 * therefore set discarding broken for each group added to a container, 1995 * whether the container is used individually or shared. This provides 1996 * us with options to allow devices within a group to opt-in and allow 1997 * discarding, so long as it is done consistently for a group (for instance 1998 * if the device is an mdev device where it is known that the host vendor 1999 * driver will never pin pages outside of the working set of the guest 2000 * driver, which would thus not be discarding candidates). 2001 * 2002 * The first opportunity to induce pinning occurs here where we attempt to 2003 * attach the group to existing containers within the AddressSpace. If any 2004 * pages are already zapped from the virtual address space, such as from 2005 * previous discards, new pinning will cause valid mappings to be 2006 * re-established. Likewise, when the overall MemoryListener for a new 2007 * container is registered, a replay of mappings within the AddressSpace 2008 * will occur, re-establishing any previously zapped pages as well. 2009 * 2010 * Especially virtio-balloon is currently only prevented from discarding 2011 * new memory, it will not yet set ram_block_discard_set_required() and 2012 * therefore, neither stops us here or deals with the sudden memory 2013 * consumption of inflated memory. 2014 * 2015 * We do support discarding of memory coordinated via the RamDiscardManager 2016 * with some IOMMU types. vfio_ram_block_discard_disable() handles the 2017 * details once we know which type of IOMMU we are using. 2018 */ 2019 2020 QLIST_FOREACH(container, &space->containers, next) { 2021 if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) { 2022 ret = vfio_ram_block_discard_disable(container, true); 2023 if (ret) { 2024 error_setg_errno(errp, -ret, 2025 "Cannot set discarding of RAM broken"); 2026 if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, 2027 &container->fd)) { 2028 error_report("vfio: error disconnecting group %d from" 2029 " container", group->groupid); 2030 } 2031 return ret; 2032 } 2033 group->container = container; 2034 QLIST_INSERT_HEAD(&container->group_list, group, container_next); 2035 vfio_kvm_device_add_group(group); 2036 return 0; 2037 } 2038 } 2039 2040 fd = qemu_open_old("/dev/vfio/vfio", O_RDWR); 2041 if (fd < 0) { 2042 error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio"); 2043 ret = -errno; 2044 goto put_space_exit; 2045 } 2046 2047 ret = ioctl(fd, VFIO_GET_API_VERSION); 2048 if (ret != VFIO_API_VERSION) { 2049 error_setg(errp, "supported vfio version: %d, " 2050 "reported version: %d", VFIO_API_VERSION, ret); 2051 ret = -EINVAL; 2052 goto close_fd_exit; 2053 } 2054 2055 container = g_malloc0(sizeof(*container)); 2056 container->space = space; 2057 container->fd = fd; 2058 container->error = NULL; 2059 container->dirty_pages_supported = false; 2060 container->dma_max_mappings = 0; 2061 QLIST_INIT(&container->giommu_list); 2062 QLIST_INIT(&container->hostwin_list); 2063 QLIST_INIT(&container->vrdl_list); 2064 2065 ret = vfio_init_container(container, group->fd, errp); 2066 if (ret) { 2067 goto free_container_exit; 2068 } 2069 2070 ret = vfio_ram_block_discard_disable(container, true); 2071 if (ret) { 2072 error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken"); 2073 goto free_container_exit; 2074 } 2075 2076 switch (container->iommu_type) { 2077 case VFIO_TYPE1v2_IOMMU: 2078 case VFIO_TYPE1_IOMMU: 2079 { 2080 struct vfio_iommu_type1_info *info; 2081 2082 /* 2083 * FIXME: This assumes that a Type1 IOMMU can map any 64-bit 2084 * IOVA whatsoever. That's not actually true, but the current 2085 * kernel interface doesn't tell us what it can map, and the 2086 * existing Type1 IOMMUs generally support any IOVA we're 2087 * going to actually try in practice. 2088 */ 2089 ret = vfio_get_iommu_info(container, &info); 2090 2091 if (ret || !(info->flags & VFIO_IOMMU_INFO_PGSIZES)) { 2092 /* Assume 4k IOVA page size */ 2093 info->iova_pgsizes = 4096; 2094 } 2095 vfio_host_win_add(container, 0, (hwaddr)-1, info->iova_pgsizes); 2096 container->pgsizes = info->iova_pgsizes; 2097 2098 /* The default in the kernel ("dma_entry_limit") is 65535. */ 2099 container->dma_max_mappings = 65535; 2100 if (!ret) { 2101 vfio_get_info_dma_avail(info, &container->dma_max_mappings); 2102 vfio_get_iommu_info_migration(container, info); 2103 } 2104 g_free(info); 2105 break; 2106 } 2107 case VFIO_SPAPR_TCE_v2_IOMMU: 2108 case VFIO_SPAPR_TCE_IOMMU: 2109 { 2110 struct vfio_iommu_spapr_tce_info info; 2111 bool v2 = container->iommu_type == VFIO_SPAPR_TCE_v2_IOMMU; 2112 2113 /* 2114 * The host kernel code implementing VFIO_IOMMU_DISABLE is called 2115 * when container fd is closed so we do not call it explicitly 2116 * in this file. 2117 */ 2118 if (!v2) { 2119 ret = ioctl(fd, VFIO_IOMMU_ENABLE); 2120 if (ret) { 2121 error_setg_errno(errp, errno, "failed to enable container"); 2122 ret = -errno; 2123 goto enable_discards_exit; 2124 } 2125 } else { 2126 container->prereg_listener = vfio_prereg_listener; 2127 2128 memory_listener_register(&container->prereg_listener, 2129 &address_space_memory); 2130 if (container->error) { 2131 memory_listener_unregister(&container->prereg_listener); 2132 ret = -1; 2133 error_propagate_prepend(errp, container->error, 2134 "RAM memory listener initialization failed: "); 2135 goto enable_discards_exit; 2136 } 2137 } 2138 2139 info.argsz = sizeof(info); 2140 ret = ioctl(fd, VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info); 2141 if (ret) { 2142 error_setg_errno(errp, errno, 2143 "VFIO_IOMMU_SPAPR_TCE_GET_INFO failed"); 2144 ret = -errno; 2145 if (v2) { 2146 memory_listener_unregister(&container->prereg_listener); 2147 } 2148 goto enable_discards_exit; 2149 } 2150 2151 if (v2) { 2152 container->pgsizes = info.ddw.pgsizes; 2153 /* 2154 * There is a default window in just created container. 2155 * To make region_add/del simpler, we better remove this 2156 * window now and let those iommu_listener callbacks 2157 * create/remove them when needed. 2158 */ 2159 ret = vfio_spapr_remove_window(container, info.dma32_window_start); 2160 if (ret) { 2161 error_setg_errno(errp, -ret, 2162 "failed to remove existing window"); 2163 goto enable_discards_exit; 2164 } 2165 } else { 2166 /* The default table uses 4K pages */ 2167 container->pgsizes = 0x1000; 2168 vfio_host_win_add(container, info.dma32_window_start, 2169 info.dma32_window_start + 2170 info.dma32_window_size - 1, 2171 0x1000); 2172 } 2173 } 2174 } 2175 2176 vfio_kvm_device_add_group(group); 2177 2178 QLIST_INIT(&container->group_list); 2179 QLIST_INSERT_HEAD(&space->containers, container, next); 2180 2181 group->container = container; 2182 QLIST_INSERT_HEAD(&container->group_list, group, container_next); 2183 2184 container->listener = vfio_memory_listener; 2185 2186 memory_listener_register(&container->listener, container->space->as); 2187 2188 if (container->error) { 2189 ret = -1; 2190 error_propagate_prepend(errp, container->error, 2191 "memory listener initialization failed: "); 2192 goto listener_release_exit; 2193 } 2194 2195 container->initialized = true; 2196 2197 return 0; 2198 listener_release_exit: 2199 QLIST_REMOVE(group, container_next); 2200 QLIST_REMOVE(container, next); 2201 vfio_kvm_device_del_group(group); 2202 vfio_listener_release(container); 2203 2204 enable_discards_exit: 2205 vfio_ram_block_discard_disable(container, false); 2206 2207 free_container_exit: 2208 g_free(container); 2209 2210 close_fd_exit: 2211 close(fd); 2212 2213 put_space_exit: 2214 vfio_put_address_space(space); 2215 2216 return ret; 2217 } 2218 2219 static void vfio_disconnect_container(VFIOGroup *group) 2220 { 2221 VFIOContainer *container = group->container; 2222 2223 QLIST_REMOVE(group, container_next); 2224 group->container = NULL; 2225 2226 /* 2227 * Explicitly release the listener first before unset container, 2228 * since unset may destroy the backend container if it's the last 2229 * group. 2230 */ 2231 if (QLIST_EMPTY(&container->group_list)) { 2232 vfio_listener_release(container); 2233 } 2234 2235 if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) { 2236 error_report("vfio: error disconnecting group %d from container", 2237 group->groupid); 2238 } 2239 2240 if (QLIST_EMPTY(&container->group_list)) { 2241 VFIOAddressSpace *space = container->space; 2242 VFIOGuestIOMMU *giommu, *tmp; 2243 VFIOHostDMAWindow *hostwin, *next; 2244 2245 QLIST_REMOVE(container, next); 2246 2247 QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) { 2248 memory_region_unregister_iommu_notifier( 2249 MEMORY_REGION(giommu->iommu), &giommu->n); 2250 QLIST_REMOVE(giommu, giommu_next); 2251 g_free(giommu); 2252 } 2253 2254 QLIST_FOREACH_SAFE(hostwin, &container->hostwin_list, hostwin_next, 2255 next) { 2256 QLIST_REMOVE(hostwin, hostwin_next); 2257 g_free(hostwin); 2258 } 2259 2260 trace_vfio_disconnect_container(container->fd); 2261 close(container->fd); 2262 g_free(container); 2263 2264 vfio_put_address_space(space); 2265 } 2266 } 2267 2268 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp) 2269 { 2270 VFIOGroup *group; 2271 char path[32]; 2272 struct vfio_group_status status = { .argsz = sizeof(status) }; 2273 2274 QLIST_FOREACH(group, &vfio_group_list, next) { 2275 if (group->groupid == groupid) { 2276 /* Found it. Now is it already in the right context? */ 2277 if (group->container->space->as == as) { 2278 return group; 2279 } else { 2280 error_setg(errp, "group %d used in multiple address spaces", 2281 group->groupid); 2282 return NULL; 2283 } 2284 } 2285 } 2286 2287 group = g_malloc0(sizeof(*group)); 2288 2289 snprintf(path, sizeof(path), "/dev/vfio/%d", groupid); 2290 group->fd = qemu_open_old(path, O_RDWR); 2291 if (group->fd < 0) { 2292 error_setg_errno(errp, errno, "failed to open %s", path); 2293 goto free_group_exit; 2294 } 2295 2296 if (ioctl(group->fd, VFIO_GROUP_GET_STATUS, &status)) { 2297 error_setg_errno(errp, errno, "failed to get group %d status", groupid); 2298 goto close_fd_exit; 2299 } 2300 2301 if (!(status.flags & VFIO_GROUP_FLAGS_VIABLE)) { 2302 error_setg(errp, "group %d is not viable", groupid); 2303 error_append_hint(errp, 2304 "Please ensure all devices within the iommu_group " 2305 "are bound to their vfio bus driver.\n"); 2306 goto close_fd_exit; 2307 } 2308 2309 group->groupid = groupid; 2310 QLIST_INIT(&group->device_list); 2311 2312 if (vfio_connect_container(group, as, errp)) { 2313 error_prepend(errp, "failed to setup container for group %d: ", 2314 groupid); 2315 goto close_fd_exit; 2316 } 2317 2318 if (QLIST_EMPTY(&vfio_group_list)) { 2319 qemu_register_reset(vfio_reset_handler, NULL); 2320 } 2321 2322 QLIST_INSERT_HEAD(&vfio_group_list, group, next); 2323 2324 return group; 2325 2326 close_fd_exit: 2327 close(group->fd); 2328 2329 free_group_exit: 2330 g_free(group); 2331 2332 return NULL; 2333 } 2334 2335 void vfio_put_group(VFIOGroup *group) 2336 { 2337 if (!group || !QLIST_EMPTY(&group->device_list)) { 2338 return; 2339 } 2340 2341 if (!group->ram_block_discard_allowed) { 2342 vfio_ram_block_discard_disable(group->container, false); 2343 } 2344 vfio_kvm_device_del_group(group); 2345 vfio_disconnect_container(group); 2346 QLIST_REMOVE(group, next); 2347 trace_vfio_put_group(group->fd); 2348 close(group->fd); 2349 g_free(group); 2350 2351 if (QLIST_EMPTY(&vfio_group_list)) { 2352 qemu_unregister_reset(vfio_reset_handler, NULL); 2353 } 2354 } 2355 2356 int vfio_get_device(VFIOGroup *group, const char *name, 2357 VFIODevice *vbasedev, Error **errp) 2358 { 2359 struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) }; 2360 int ret, fd; 2361 2362 fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name); 2363 if (fd < 0) { 2364 error_setg_errno(errp, errno, "error getting device from group %d", 2365 group->groupid); 2366 error_append_hint(errp, 2367 "Verify all devices in group %d are bound to vfio-<bus> " 2368 "or pci-stub and not already in use\n", group->groupid); 2369 return fd; 2370 } 2371 2372 ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info); 2373 if (ret) { 2374 error_setg_errno(errp, errno, "error getting device info"); 2375 close(fd); 2376 return ret; 2377 } 2378 2379 /* 2380 * Set discarding of RAM as not broken for this group if the driver knows 2381 * the device operates compatibly with discarding. Setting must be 2382 * consistent per group, but since compatibility is really only possible 2383 * with mdev currently, we expect singleton groups. 2384 */ 2385 if (vbasedev->ram_block_discard_allowed != 2386 group->ram_block_discard_allowed) { 2387 if (!QLIST_EMPTY(&group->device_list)) { 2388 error_setg(errp, "Inconsistent setting of support for discarding " 2389 "RAM (e.g., balloon) within group"); 2390 close(fd); 2391 return -1; 2392 } 2393 2394 if (!group->ram_block_discard_allowed) { 2395 group->ram_block_discard_allowed = true; 2396 vfio_ram_block_discard_disable(group->container, false); 2397 } 2398 } 2399 2400 vbasedev->fd = fd; 2401 vbasedev->group = group; 2402 QLIST_INSERT_HEAD(&group->device_list, vbasedev, next); 2403 2404 vbasedev->num_irqs = dev_info.num_irqs; 2405 vbasedev->num_regions = dev_info.num_regions; 2406 vbasedev->flags = dev_info.flags; 2407 2408 trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions, 2409 dev_info.num_irqs); 2410 2411 vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET); 2412 return 0; 2413 } 2414 2415 void vfio_put_base_device(VFIODevice *vbasedev) 2416 { 2417 if (!vbasedev->group) { 2418 return; 2419 } 2420 QLIST_REMOVE(vbasedev, next); 2421 vbasedev->group = NULL; 2422 trace_vfio_put_base_device(vbasedev->fd); 2423 close(vbasedev->fd); 2424 } 2425 2426 int vfio_get_region_info(VFIODevice *vbasedev, int index, 2427 struct vfio_region_info **info) 2428 { 2429 size_t argsz = sizeof(struct vfio_region_info); 2430 2431 *info = g_malloc0(argsz); 2432 2433 (*info)->index = index; 2434 retry: 2435 (*info)->argsz = argsz; 2436 2437 if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) { 2438 g_free(*info); 2439 *info = NULL; 2440 return -errno; 2441 } 2442 2443 if ((*info)->argsz > argsz) { 2444 argsz = (*info)->argsz; 2445 *info = g_realloc(*info, argsz); 2446 2447 goto retry; 2448 } 2449 2450 return 0; 2451 } 2452 2453 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type, 2454 uint32_t subtype, struct vfio_region_info **info) 2455 { 2456 int i; 2457 2458 for (i = 0; i < vbasedev->num_regions; i++) { 2459 struct vfio_info_cap_header *hdr; 2460 struct vfio_region_info_cap_type *cap_type; 2461 2462 if (vfio_get_region_info(vbasedev, i, info)) { 2463 continue; 2464 } 2465 2466 hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE); 2467 if (!hdr) { 2468 g_free(*info); 2469 continue; 2470 } 2471 2472 cap_type = container_of(hdr, struct vfio_region_info_cap_type, header); 2473 2474 trace_vfio_get_dev_region(vbasedev->name, i, 2475 cap_type->type, cap_type->subtype); 2476 2477 if (cap_type->type == type && cap_type->subtype == subtype) { 2478 return 0; 2479 } 2480 2481 g_free(*info); 2482 } 2483 2484 *info = NULL; 2485 return -ENODEV; 2486 } 2487 2488 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type) 2489 { 2490 struct vfio_region_info *info = NULL; 2491 bool ret = false; 2492 2493 if (!vfio_get_region_info(vbasedev, region, &info)) { 2494 if (vfio_get_region_info_cap(info, cap_type)) { 2495 ret = true; 2496 } 2497 g_free(info); 2498 } 2499 2500 return ret; 2501 } 2502 2503 /* 2504 * Interfaces for IBM EEH (Enhanced Error Handling) 2505 */ 2506 static bool vfio_eeh_container_ok(VFIOContainer *container) 2507 { 2508 /* 2509 * As of 2016-03-04 (linux-4.5) the host kernel EEH/VFIO 2510 * implementation is broken if there are multiple groups in a 2511 * container. The hardware works in units of Partitionable 2512 * Endpoints (== IOMMU groups) and the EEH operations naively 2513 * iterate across all groups in the container, without any logic 2514 * to make sure the groups have their state synchronized. For 2515 * certain operations (ENABLE) that might be ok, until an error 2516 * occurs, but for others (GET_STATE) it's clearly broken. 2517 */ 2518 2519 /* 2520 * XXX Once fixed kernels exist, test for them here 2521 */ 2522 2523 if (QLIST_EMPTY(&container->group_list)) { 2524 return false; 2525 } 2526 2527 if (QLIST_NEXT(QLIST_FIRST(&container->group_list), container_next)) { 2528 return false; 2529 } 2530 2531 return true; 2532 } 2533 2534 static int vfio_eeh_container_op(VFIOContainer *container, uint32_t op) 2535 { 2536 struct vfio_eeh_pe_op pe_op = { 2537 .argsz = sizeof(pe_op), 2538 .op = op, 2539 }; 2540 int ret; 2541 2542 if (!vfio_eeh_container_ok(container)) { 2543 error_report("vfio/eeh: EEH_PE_OP 0x%x: " 2544 "kernel requires a container with exactly one group", op); 2545 return -EPERM; 2546 } 2547 2548 ret = ioctl(container->fd, VFIO_EEH_PE_OP, &pe_op); 2549 if (ret < 0) { 2550 error_report("vfio/eeh: EEH_PE_OP 0x%x failed: %m", op); 2551 return -errno; 2552 } 2553 2554 return ret; 2555 } 2556 2557 static VFIOContainer *vfio_eeh_as_container(AddressSpace *as) 2558 { 2559 VFIOAddressSpace *space = vfio_get_address_space(as); 2560 VFIOContainer *container = NULL; 2561 2562 if (QLIST_EMPTY(&space->containers)) { 2563 /* No containers to act on */ 2564 goto out; 2565 } 2566 2567 container = QLIST_FIRST(&space->containers); 2568 2569 if (QLIST_NEXT(container, next)) { 2570 /* We don't yet have logic to synchronize EEH state across 2571 * multiple containers */ 2572 container = NULL; 2573 goto out; 2574 } 2575 2576 out: 2577 vfio_put_address_space(space); 2578 return container; 2579 } 2580 2581 bool vfio_eeh_as_ok(AddressSpace *as) 2582 { 2583 VFIOContainer *container = vfio_eeh_as_container(as); 2584 2585 return (container != NULL) && vfio_eeh_container_ok(container); 2586 } 2587 2588 int vfio_eeh_as_op(AddressSpace *as, uint32_t op) 2589 { 2590 VFIOContainer *container = vfio_eeh_as_container(as); 2591 2592 if (!container) { 2593 return -ENODEV; 2594 } 2595 return vfio_eeh_container_op(container, op); 2596 } 2597