1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Red Hat, Inc. All rights reserved. 4 * Author: Alex Williamson <alex.williamson@redhat.com> 5 * 6 * Derived from original vfio: 7 * Copyright 2010 Cisco Systems, Inc. All rights reserved. 8 * Author: Tom Lyon, pugs@cisco.com 9 */ 10 11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 13 #include <linux/device.h> 14 #include <linux/eventfd.h> 15 #include <linux/file.h> 16 #include <linux/interrupt.h> 17 #include <linux/iommu.h> 18 #include <linux/module.h> 19 #include <linux/mutex.h> 20 #include <linux/notifier.h> 21 #include <linux/pci.h> 22 #include <linux/pm_runtime.h> 23 #include <linux/slab.h> 24 #include <linux/types.h> 25 #include <linux/uaccess.h> 26 #include <linux/vgaarb.h> 27 #include <linux/nospec.h> 28 #include <linux/sched/mm.h> 29 30 #include <linux/vfio_pci_core.h> 31 32 #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>" 33 #define DRIVER_DESC "core driver for VFIO based PCI devices" 34 35 static bool nointxmask; 36 static bool disable_vga; 37 static bool disable_idle_d3; 38 39 static inline bool vfio_vga_disabled(void) 40 { 41 #ifdef CONFIG_VFIO_PCI_VGA 42 return disable_vga; 43 #else 44 return true; 45 #endif 46 } 47 48 /* 49 * Our VGA arbiter participation is limited since we don't know anything 50 * about the device itself. However, if the device is the only VGA device 51 * downstream of a bridge and VFIO VGA support is disabled, then we can 52 * safely return legacy VGA IO and memory as not decoded since the user 53 * has no way to get to it and routing can be disabled externally at the 54 * bridge. 55 */ 56 static unsigned int vfio_pci_set_decode(struct pci_dev *pdev, bool single_vga) 57 { 58 struct pci_dev *tmp = NULL; 59 unsigned char max_busnr; 60 unsigned int decodes; 61 62 if (single_vga || !vfio_vga_disabled() || pci_is_root_bus(pdev->bus)) 63 return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM | 64 VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; 65 66 max_busnr = pci_bus_max_busnr(pdev->bus); 67 decodes = VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; 68 69 while ((tmp = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, tmp)) != NULL) { 70 if (tmp == pdev || 71 pci_domain_nr(tmp->bus) != pci_domain_nr(pdev->bus) || 72 pci_is_root_bus(tmp->bus)) 73 continue; 74 75 if (tmp->bus->number >= pdev->bus->number && 76 tmp->bus->number <= max_busnr) { 77 pci_dev_put(tmp); 78 decodes |= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; 79 break; 80 } 81 } 82 83 return decodes; 84 } 85 86 static void vfio_pci_probe_mmaps(struct vfio_pci_core_device *vdev) 87 { 88 struct resource *res; 89 int i; 90 struct vfio_pci_dummy_resource *dummy_res; 91 92 for (i = 0; i < PCI_STD_NUM_BARS; i++) { 93 int bar = i + PCI_STD_RESOURCES; 94 95 res = &vdev->pdev->resource[bar]; 96 97 if (!IS_ENABLED(CONFIG_VFIO_PCI_MMAP)) 98 goto no_mmap; 99 100 if (!(res->flags & IORESOURCE_MEM)) 101 goto no_mmap; 102 103 /* 104 * The PCI core shouldn't set up a resource with a 105 * type but zero size. But there may be bugs that 106 * cause us to do that. 107 */ 108 if (!resource_size(res)) 109 goto no_mmap; 110 111 if (resource_size(res) >= PAGE_SIZE) { 112 vdev->bar_mmap_supported[bar] = true; 113 continue; 114 } 115 116 if (!(res->start & ~PAGE_MASK)) { 117 /* 118 * Add a dummy resource to reserve the remainder 119 * of the exclusive page in case that hot-add 120 * device's bar is assigned into it. 121 */ 122 dummy_res = kzalloc(sizeof(*dummy_res), GFP_KERNEL); 123 if (dummy_res == NULL) 124 goto no_mmap; 125 126 dummy_res->resource.name = "vfio sub-page reserved"; 127 dummy_res->resource.start = res->end + 1; 128 dummy_res->resource.end = res->start + PAGE_SIZE - 1; 129 dummy_res->resource.flags = res->flags; 130 if (request_resource(res->parent, 131 &dummy_res->resource)) { 132 kfree(dummy_res); 133 goto no_mmap; 134 } 135 dummy_res->index = bar; 136 list_add(&dummy_res->res_next, 137 &vdev->dummy_resources_list); 138 vdev->bar_mmap_supported[bar] = true; 139 continue; 140 } 141 /* 142 * Here we don't handle the case when the BAR is not page 143 * aligned because we can't expect the BAR will be 144 * assigned into the same location in a page in guest 145 * when we passthrough the BAR. And it's hard to access 146 * this BAR in userspace because we have no way to get 147 * the BAR's location in a page. 148 */ 149 no_mmap: 150 vdev->bar_mmap_supported[bar] = false; 151 } 152 } 153 154 struct vfio_pci_group_info; 155 static bool vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set); 156 static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, 157 struct vfio_pci_group_info *groups); 158 159 /* 160 * INTx masking requires the ability to disable INTx signaling via PCI_COMMAND 161 * _and_ the ability detect when the device is asserting INTx via PCI_STATUS. 162 * If a device implements the former but not the latter we would typically 163 * expect broken_intx_masking be set and require an exclusive interrupt. 164 * However since we do have control of the device's ability to assert INTx, 165 * we can instead pretend that the device does not implement INTx, virtualizing 166 * the pin register to report zero and maintaining DisINTx set on the host. 167 */ 168 static bool vfio_pci_nointx(struct pci_dev *pdev) 169 { 170 switch (pdev->vendor) { 171 case PCI_VENDOR_ID_INTEL: 172 switch (pdev->device) { 173 /* All i40e (XL710/X710/XXV710) 10/20/25/40GbE NICs */ 174 case 0x1572: 175 case 0x1574: 176 case 0x1580 ... 0x1581: 177 case 0x1583 ... 0x158b: 178 case 0x37d0 ... 0x37d2: 179 /* X550 */ 180 case 0x1563: 181 return true; 182 default: 183 return false; 184 } 185 } 186 187 return false; 188 } 189 190 static void vfio_pci_probe_power_state(struct vfio_pci_core_device *vdev) 191 { 192 struct pci_dev *pdev = vdev->pdev; 193 u16 pmcsr; 194 195 if (!pdev->pm_cap) 196 return; 197 198 pci_read_config_word(pdev, pdev->pm_cap + PCI_PM_CTRL, &pmcsr); 199 200 vdev->needs_pm_restore = !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET); 201 } 202 203 /* 204 * pci_set_power_state() wrapper handling devices which perform a soft reset on 205 * D3->D0 transition. Save state prior to D0/1/2->D3, stash it on the vdev, 206 * restore when returned to D0. Saved separately from pci_saved_state for use 207 * by PM capability emulation and separately from pci_dev internal saved state 208 * to avoid it being overwritten and consumed around other resets. 209 */ 210 int vfio_pci_set_power_state(struct vfio_pci_core_device *vdev, pci_power_t state) 211 { 212 struct pci_dev *pdev = vdev->pdev; 213 bool needs_restore = false, needs_save = false; 214 int ret; 215 216 if (vdev->needs_pm_restore) { 217 if (pdev->current_state < PCI_D3hot && state >= PCI_D3hot) { 218 pci_save_state(pdev); 219 needs_save = true; 220 } 221 222 if (pdev->current_state >= PCI_D3hot && state <= PCI_D0) 223 needs_restore = true; 224 } 225 226 ret = pci_set_power_state(pdev, state); 227 228 if (!ret) { 229 /* D3 might be unsupported via quirk, skip unless in D3 */ 230 if (needs_save && pdev->current_state >= PCI_D3hot) { 231 vdev->pm_save = pci_store_saved_state(pdev); 232 } else if (needs_restore) { 233 pci_load_and_free_saved_state(pdev, &vdev->pm_save); 234 pci_restore_state(pdev); 235 } 236 } 237 238 return ret; 239 } 240 241 int vfio_pci_core_enable(struct vfio_pci_core_device *vdev) 242 { 243 struct pci_dev *pdev = vdev->pdev; 244 int ret; 245 u16 cmd; 246 u8 msix_pos; 247 248 vfio_pci_set_power_state(vdev, PCI_D0); 249 250 /* Don't allow our initial saved state to include busmaster */ 251 pci_clear_master(pdev); 252 253 ret = pci_enable_device(pdev); 254 if (ret) 255 return ret; 256 257 /* If reset fails because of the device lock, fail this path entirely */ 258 ret = pci_try_reset_function(pdev); 259 if (ret == -EAGAIN) { 260 pci_disable_device(pdev); 261 return ret; 262 } 263 264 vdev->reset_works = !ret; 265 pci_save_state(pdev); 266 vdev->pci_saved_state = pci_store_saved_state(pdev); 267 if (!vdev->pci_saved_state) 268 pci_dbg(pdev, "%s: Couldn't store saved state\n", __func__); 269 270 if (likely(!nointxmask)) { 271 if (vfio_pci_nointx(pdev)) { 272 pci_info(pdev, "Masking broken INTx support\n"); 273 vdev->nointx = true; 274 pci_intx(pdev, 0); 275 } else 276 vdev->pci_2_3 = pci_intx_mask_supported(pdev); 277 } 278 279 pci_read_config_word(pdev, PCI_COMMAND, &cmd); 280 if (vdev->pci_2_3 && (cmd & PCI_COMMAND_INTX_DISABLE)) { 281 cmd &= ~PCI_COMMAND_INTX_DISABLE; 282 pci_write_config_word(pdev, PCI_COMMAND, cmd); 283 } 284 285 ret = vfio_config_init(vdev); 286 if (ret) { 287 kfree(vdev->pci_saved_state); 288 vdev->pci_saved_state = NULL; 289 pci_disable_device(pdev); 290 return ret; 291 } 292 293 msix_pos = pdev->msix_cap; 294 if (msix_pos) { 295 u16 flags; 296 u32 table; 297 298 pci_read_config_word(pdev, msix_pos + PCI_MSIX_FLAGS, &flags); 299 pci_read_config_dword(pdev, msix_pos + PCI_MSIX_TABLE, &table); 300 301 vdev->msix_bar = table & PCI_MSIX_TABLE_BIR; 302 vdev->msix_offset = table & PCI_MSIX_TABLE_OFFSET; 303 vdev->msix_size = ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) * 16; 304 } else 305 vdev->msix_bar = 0xFF; 306 307 if (!vfio_vga_disabled() && vfio_pci_is_vga(pdev)) 308 vdev->has_vga = true; 309 310 311 return 0; 312 } 313 EXPORT_SYMBOL_GPL(vfio_pci_core_enable); 314 315 void vfio_pci_core_disable(struct vfio_pci_core_device *vdev) 316 { 317 struct pci_dev *pdev = vdev->pdev; 318 struct vfio_pci_dummy_resource *dummy_res, *tmp; 319 struct vfio_pci_ioeventfd *ioeventfd, *ioeventfd_tmp; 320 int i, bar; 321 322 /* For needs_reset */ 323 lockdep_assert_held(&vdev->vdev.dev_set->lock); 324 325 /* Stop the device from further DMA */ 326 pci_clear_master(pdev); 327 328 vfio_pci_set_irqs_ioctl(vdev, VFIO_IRQ_SET_DATA_NONE | 329 VFIO_IRQ_SET_ACTION_TRIGGER, 330 vdev->irq_type, 0, 0, NULL); 331 332 /* Device closed, don't need mutex here */ 333 list_for_each_entry_safe(ioeventfd, ioeventfd_tmp, 334 &vdev->ioeventfds_list, next) { 335 vfio_virqfd_disable(&ioeventfd->virqfd); 336 list_del(&ioeventfd->next); 337 kfree(ioeventfd); 338 } 339 vdev->ioeventfds_nr = 0; 340 341 vdev->virq_disabled = false; 342 343 for (i = 0; i < vdev->num_regions; i++) 344 vdev->region[i].ops->release(vdev, &vdev->region[i]); 345 346 vdev->num_regions = 0; 347 kfree(vdev->region); 348 vdev->region = NULL; /* don't krealloc a freed pointer */ 349 350 vfio_config_free(vdev); 351 352 for (i = 0; i < PCI_STD_NUM_BARS; i++) { 353 bar = i + PCI_STD_RESOURCES; 354 if (!vdev->barmap[bar]) 355 continue; 356 pci_iounmap(pdev, vdev->barmap[bar]); 357 pci_release_selected_regions(pdev, 1 << bar); 358 vdev->barmap[bar] = NULL; 359 } 360 361 list_for_each_entry_safe(dummy_res, tmp, 362 &vdev->dummy_resources_list, res_next) { 363 list_del(&dummy_res->res_next); 364 release_resource(&dummy_res->resource); 365 kfree(dummy_res); 366 } 367 368 vdev->needs_reset = true; 369 370 /* 371 * If we have saved state, restore it. If we can reset the device, 372 * even better. Resetting with current state seems better than 373 * nothing, but saving and restoring current state without reset 374 * is just busy work. 375 */ 376 if (pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state)) { 377 pci_info(pdev, "%s: Couldn't reload saved state\n", __func__); 378 379 if (!vdev->reset_works) 380 goto out; 381 382 pci_save_state(pdev); 383 } 384 385 /* 386 * Disable INTx and MSI, presumably to avoid spurious interrupts 387 * during reset. Stolen from pci_reset_function() 388 */ 389 pci_write_config_word(pdev, PCI_COMMAND, PCI_COMMAND_INTX_DISABLE); 390 391 /* 392 * Try to get the locks ourselves to prevent a deadlock. The 393 * success of this is dependent on being able to lock the device, 394 * which is not always possible. 395 * We can not use the "try" reset interface here, which will 396 * overwrite the previously restored configuration information. 397 */ 398 if (vdev->reset_works && pci_dev_trylock(pdev)) { 399 if (!__pci_reset_function_locked(pdev)) 400 vdev->needs_reset = false; 401 pci_dev_unlock(pdev); 402 } 403 404 pci_restore_state(pdev); 405 out: 406 pci_disable_device(pdev); 407 408 if (!vfio_pci_dev_set_try_reset(vdev->vdev.dev_set) && !disable_idle_d3) 409 vfio_pci_set_power_state(vdev, PCI_D3hot); 410 } 411 EXPORT_SYMBOL_GPL(vfio_pci_core_disable); 412 413 static struct vfio_pci_core_device *get_pf_vdev(struct vfio_pci_core_device *vdev) 414 { 415 struct pci_dev *physfn = pci_physfn(vdev->pdev); 416 struct vfio_device *pf_dev; 417 418 if (!vdev->pdev->is_virtfn) 419 return NULL; 420 421 pf_dev = vfio_device_get_from_dev(&physfn->dev); 422 if (!pf_dev) 423 return NULL; 424 425 if (pci_dev_driver(physfn) != pci_dev_driver(vdev->pdev)) { 426 vfio_device_put(pf_dev); 427 return NULL; 428 } 429 430 return container_of(pf_dev, struct vfio_pci_core_device, vdev); 431 } 432 433 static void vfio_pci_vf_token_user_add(struct vfio_pci_core_device *vdev, int val) 434 { 435 struct vfio_pci_core_device *pf_vdev = get_pf_vdev(vdev); 436 437 if (!pf_vdev) 438 return; 439 440 mutex_lock(&pf_vdev->vf_token->lock); 441 pf_vdev->vf_token->users += val; 442 WARN_ON(pf_vdev->vf_token->users < 0); 443 mutex_unlock(&pf_vdev->vf_token->lock); 444 445 vfio_device_put(&pf_vdev->vdev); 446 } 447 448 void vfio_pci_core_close_device(struct vfio_device *core_vdev) 449 { 450 struct vfio_pci_core_device *vdev = 451 container_of(core_vdev, struct vfio_pci_core_device, vdev); 452 453 vfio_pci_vf_token_user_add(vdev, -1); 454 vfio_spapr_pci_eeh_release(vdev->pdev); 455 vfio_pci_core_disable(vdev); 456 457 mutex_lock(&vdev->igate); 458 if (vdev->err_trigger) { 459 eventfd_ctx_put(vdev->err_trigger); 460 vdev->err_trigger = NULL; 461 } 462 if (vdev->req_trigger) { 463 eventfd_ctx_put(vdev->req_trigger); 464 vdev->req_trigger = NULL; 465 } 466 mutex_unlock(&vdev->igate); 467 } 468 EXPORT_SYMBOL_GPL(vfio_pci_core_close_device); 469 470 void vfio_pci_core_finish_enable(struct vfio_pci_core_device *vdev) 471 { 472 vfio_pci_probe_mmaps(vdev); 473 vfio_spapr_pci_eeh_open(vdev->pdev); 474 vfio_pci_vf_token_user_add(vdev, 1); 475 } 476 EXPORT_SYMBOL_GPL(vfio_pci_core_finish_enable); 477 478 static int vfio_pci_get_irq_count(struct vfio_pci_core_device *vdev, int irq_type) 479 { 480 if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) { 481 u8 pin; 482 483 if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || 484 vdev->nointx || vdev->pdev->is_virtfn) 485 return 0; 486 487 pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin); 488 489 return pin ? 1 : 0; 490 } else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) { 491 u8 pos; 492 u16 flags; 493 494 pos = vdev->pdev->msi_cap; 495 if (pos) { 496 pci_read_config_word(vdev->pdev, 497 pos + PCI_MSI_FLAGS, &flags); 498 return 1 << ((flags & PCI_MSI_FLAGS_QMASK) >> 1); 499 } 500 } else if (irq_type == VFIO_PCI_MSIX_IRQ_INDEX) { 501 u8 pos; 502 u16 flags; 503 504 pos = vdev->pdev->msix_cap; 505 if (pos) { 506 pci_read_config_word(vdev->pdev, 507 pos + PCI_MSIX_FLAGS, &flags); 508 509 return (flags & PCI_MSIX_FLAGS_QSIZE) + 1; 510 } 511 } else if (irq_type == VFIO_PCI_ERR_IRQ_INDEX) { 512 if (pci_is_pcie(vdev->pdev)) 513 return 1; 514 } else if (irq_type == VFIO_PCI_REQ_IRQ_INDEX) { 515 return 1; 516 } 517 518 return 0; 519 } 520 521 static int vfio_pci_count_devs(struct pci_dev *pdev, void *data) 522 { 523 (*(int *)data)++; 524 return 0; 525 } 526 527 struct vfio_pci_fill_info { 528 int max; 529 int cur; 530 struct vfio_pci_dependent_device *devices; 531 }; 532 533 static int vfio_pci_fill_devs(struct pci_dev *pdev, void *data) 534 { 535 struct vfio_pci_fill_info *fill = data; 536 struct iommu_group *iommu_group; 537 538 if (fill->cur == fill->max) 539 return -EAGAIN; /* Something changed, try again */ 540 541 iommu_group = iommu_group_get(&pdev->dev); 542 if (!iommu_group) 543 return -EPERM; /* Cannot reset non-isolated devices */ 544 545 fill->devices[fill->cur].group_id = iommu_group_id(iommu_group); 546 fill->devices[fill->cur].segment = pci_domain_nr(pdev->bus); 547 fill->devices[fill->cur].bus = pdev->bus->number; 548 fill->devices[fill->cur].devfn = pdev->devfn; 549 fill->cur++; 550 iommu_group_put(iommu_group); 551 return 0; 552 } 553 554 struct vfio_pci_group_info { 555 int count; 556 struct vfio_group **groups; 557 }; 558 559 static bool vfio_pci_dev_below_slot(struct pci_dev *pdev, struct pci_slot *slot) 560 { 561 for (; pdev; pdev = pdev->bus->self) 562 if (pdev->bus == slot->bus) 563 return (pdev->slot == slot); 564 return false; 565 } 566 567 struct vfio_pci_walk_info { 568 int (*fn)(struct pci_dev *pdev, void *data); 569 void *data; 570 struct pci_dev *pdev; 571 bool slot; 572 int ret; 573 }; 574 575 static int vfio_pci_walk_wrapper(struct pci_dev *pdev, void *data) 576 { 577 struct vfio_pci_walk_info *walk = data; 578 579 if (!walk->slot || vfio_pci_dev_below_slot(pdev, walk->pdev->slot)) 580 walk->ret = walk->fn(pdev, walk->data); 581 582 return walk->ret; 583 } 584 585 static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev, 586 int (*fn)(struct pci_dev *, 587 void *data), void *data, 588 bool slot) 589 { 590 struct vfio_pci_walk_info walk = { 591 .fn = fn, .data = data, .pdev = pdev, .slot = slot, .ret = 0, 592 }; 593 594 pci_walk_bus(pdev->bus, vfio_pci_walk_wrapper, &walk); 595 596 return walk.ret; 597 } 598 599 static int msix_mmappable_cap(struct vfio_pci_core_device *vdev, 600 struct vfio_info_cap *caps) 601 { 602 struct vfio_info_cap_header header = { 603 .id = VFIO_REGION_INFO_CAP_MSIX_MAPPABLE, 604 .version = 1 605 }; 606 607 return vfio_info_add_capability(caps, &header, sizeof(header)); 608 } 609 610 int vfio_pci_register_dev_region(struct vfio_pci_core_device *vdev, 611 unsigned int type, unsigned int subtype, 612 const struct vfio_pci_regops *ops, 613 size_t size, u32 flags, void *data) 614 { 615 struct vfio_pci_region *region; 616 617 region = krealloc(vdev->region, 618 (vdev->num_regions + 1) * sizeof(*region), 619 GFP_KERNEL); 620 if (!region) 621 return -ENOMEM; 622 623 vdev->region = region; 624 vdev->region[vdev->num_regions].type = type; 625 vdev->region[vdev->num_regions].subtype = subtype; 626 vdev->region[vdev->num_regions].ops = ops; 627 vdev->region[vdev->num_regions].size = size; 628 vdev->region[vdev->num_regions].flags = flags; 629 vdev->region[vdev->num_regions].data = data; 630 631 vdev->num_regions++; 632 633 return 0; 634 } 635 EXPORT_SYMBOL_GPL(vfio_pci_register_dev_region); 636 637 long vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd, 638 unsigned long arg) 639 { 640 struct vfio_pci_core_device *vdev = 641 container_of(core_vdev, struct vfio_pci_core_device, vdev); 642 unsigned long minsz; 643 644 if (cmd == VFIO_DEVICE_GET_INFO) { 645 struct vfio_device_info info; 646 struct vfio_info_cap caps = { .buf = NULL, .size = 0 }; 647 unsigned long capsz; 648 int ret; 649 650 minsz = offsetofend(struct vfio_device_info, num_irqs); 651 652 /* For backward compatibility, cannot require this */ 653 capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset); 654 655 if (copy_from_user(&info, (void __user *)arg, minsz)) 656 return -EFAULT; 657 658 if (info.argsz < minsz) 659 return -EINVAL; 660 661 if (info.argsz >= capsz) { 662 minsz = capsz; 663 info.cap_offset = 0; 664 } 665 666 info.flags = VFIO_DEVICE_FLAGS_PCI; 667 668 if (vdev->reset_works) 669 info.flags |= VFIO_DEVICE_FLAGS_RESET; 670 671 info.num_regions = VFIO_PCI_NUM_REGIONS + vdev->num_regions; 672 info.num_irqs = VFIO_PCI_NUM_IRQS; 673 674 ret = vfio_pci_info_zdev_add_caps(vdev, &caps); 675 if (ret && ret != -ENODEV) { 676 pci_warn(vdev->pdev, "Failed to setup zPCI info capabilities\n"); 677 return ret; 678 } 679 680 if (caps.size) { 681 info.flags |= VFIO_DEVICE_FLAGS_CAPS; 682 if (info.argsz < sizeof(info) + caps.size) { 683 info.argsz = sizeof(info) + caps.size; 684 } else { 685 vfio_info_cap_shift(&caps, sizeof(info)); 686 if (copy_to_user((void __user *)arg + 687 sizeof(info), caps.buf, 688 caps.size)) { 689 kfree(caps.buf); 690 return -EFAULT; 691 } 692 info.cap_offset = sizeof(info); 693 } 694 695 kfree(caps.buf); 696 } 697 698 return copy_to_user((void __user *)arg, &info, minsz) ? 699 -EFAULT : 0; 700 701 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) { 702 struct pci_dev *pdev = vdev->pdev; 703 struct vfio_region_info info; 704 struct vfio_info_cap caps = { .buf = NULL, .size = 0 }; 705 int i, ret; 706 707 minsz = offsetofend(struct vfio_region_info, offset); 708 709 if (copy_from_user(&info, (void __user *)arg, minsz)) 710 return -EFAULT; 711 712 if (info.argsz < minsz) 713 return -EINVAL; 714 715 switch (info.index) { 716 case VFIO_PCI_CONFIG_REGION_INDEX: 717 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 718 info.size = pdev->cfg_size; 719 info.flags = VFIO_REGION_INFO_FLAG_READ | 720 VFIO_REGION_INFO_FLAG_WRITE; 721 break; 722 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: 723 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 724 info.size = pci_resource_len(pdev, info.index); 725 if (!info.size) { 726 info.flags = 0; 727 break; 728 } 729 730 info.flags = VFIO_REGION_INFO_FLAG_READ | 731 VFIO_REGION_INFO_FLAG_WRITE; 732 if (vdev->bar_mmap_supported[info.index]) { 733 info.flags |= VFIO_REGION_INFO_FLAG_MMAP; 734 if (info.index == vdev->msix_bar) { 735 ret = msix_mmappable_cap(vdev, &caps); 736 if (ret) 737 return ret; 738 } 739 } 740 741 break; 742 case VFIO_PCI_ROM_REGION_INDEX: 743 { 744 void __iomem *io; 745 size_t size; 746 u16 cmd; 747 748 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 749 info.flags = 0; 750 751 /* Report the BAR size, not the ROM size */ 752 info.size = pci_resource_len(pdev, info.index); 753 if (!info.size) { 754 /* Shadow ROMs appear as PCI option ROMs */ 755 if (pdev->resource[PCI_ROM_RESOURCE].flags & 756 IORESOURCE_ROM_SHADOW) 757 info.size = 0x20000; 758 else 759 break; 760 } 761 762 /* 763 * Is it really there? Enable memory decode for 764 * implicit access in pci_map_rom(). 765 */ 766 cmd = vfio_pci_memory_lock_and_enable(vdev); 767 io = pci_map_rom(pdev, &size); 768 if (io) { 769 info.flags = VFIO_REGION_INFO_FLAG_READ; 770 pci_unmap_rom(pdev, io); 771 } else { 772 info.size = 0; 773 } 774 vfio_pci_memory_unlock_and_restore(vdev, cmd); 775 776 break; 777 } 778 case VFIO_PCI_VGA_REGION_INDEX: 779 if (!vdev->has_vga) 780 return -EINVAL; 781 782 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 783 info.size = 0xc0000; 784 info.flags = VFIO_REGION_INFO_FLAG_READ | 785 VFIO_REGION_INFO_FLAG_WRITE; 786 787 break; 788 default: 789 { 790 struct vfio_region_info_cap_type cap_type = { 791 .header.id = VFIO_REGION_INFO_CAP_TYPE, 792 .header.version = 1 }; 793 794 if (info.index >= 795 VFIO_PCI_NUM_REGIONS + vdev->num_regions) 796 return -EINVAL; 797 info.index = array_index_nospec(info.index, 798 VFIO_PCI_NUM_REGIONS + 799 vdev->num_regions); 800 801 i = info.index - VFIO_PCI_NUM_REGIONS; 802 803 info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); 804 info.size = vdev->region[i].size; 805 info.flags = vdev->region[i].flags; 806 807 cap_type.type = vdev->region[i].type; 808 cap_type.subtype = vdev->region[i].subtype; 809 810 ret = vfio_info_add_capability(&caps, &cap_type.header, 811 sizeof(cap_type)); 812 if (ret) 813 return ret; 814 815 if (vdev->region[i].ops->add_capability) { 816 ret = vdev->region[i].ops->add_capability(vdev, 817 &vdev->region[i], &caps); 818 if (ret) 819 return ret; 820 } 821 } 822 } 823 824 if (caps.size) { 825 info.flags |= VFIO_REGION_INFO_FLAG_CAPS; 826 if (info.argsz < sizeof(info) + caps.size) { 827 info.argsz = sizeof(info) + caps.size; 828 info.cap_offset = 0; 829 } else { 830 vfio_info_cap_shift(&caps, sizeof(info)); 831 if (copy_to_user((void __user *)arg + 832 sizeof(info), caps.buf, 833 caps.size)) { 834 kfree(caps.buf); 835 return -EFAULT; 836 } 837 info.cap_offset = sizeof(info); 838 } 839 840 kfree(caps.buf); 841 } 842 843 return copy_to_user((void __user *)arg, &info, minsz) ? 844 -EFAULT : 0; 845 846 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) { 847 struct vfio_irq_info info; 848 849 minsz = offsetofend(struct vfio_irq_info, count); 850 851 if (copy_from_user(&info, (void __user *)arg, minsz)) 852 return -EFAULT; 853 854 if (info.argsz < minsz || info.index >= VFIO_PCI_NUM_IRQS) 855 return -EINVAL; 856 857 switch (info.index) { 858 case VFIO_PCI_INTX_IRQ_INDEX ... VFIO_PCI_MSIX_IRQ_INDEX: 859 case VFIO_PCI_REQ_IRQ_INDEX: 860 break; 861 case VFIO_PCI_ERR_IRQ_INDEX: 862 if (pci_is_pcie(vdev->pdev)) 863 break; 864 fallthrough; 865 default: 866 return -EINVAL; 867 } 868 869 info.flags = VFIO_IRQ_INFO_EVENTFD; 870 871 info.count = vfio_pci_get_irq_count(vdev, info.index); 872 873 if (info.index == VFIO_PCI_INTX_IRQ_INDEX) 874 info.flags |= (VFIO_IRQ_INFO_MASKABLE | 875 VFIO_IRQ_INFO_AUTOMASKED); 876 else 877 info.flags |= VFIO_IRQ_INFO_NORESIZE; 878 879 return copy_to_user((void __user *)arg, &info, minsz) ? 880 -EFAULT : 0; 881 882 } else if (cmd == VFIO_DEVICE_SET_IRQS) { 883 struct vfio_irq_set hdr; 884 u8 *data = NULL; 885 int max, ret = 0; 886 size_t data_size = 0; 887 888 minsz = offsetofend(struct vfio_irq_set, count); 889 890 if (copy_from_user(&hdr, (void __user *)arg, minsz)) 891 return -EFAULT; 892 893 max = vfio_pci_get_irq_count(vdev, hdr.index); 894 895 ret = vfio_set_irqs_validate_and_prepare(&hdr, max, 896 VFIO_PCI_NUM_IRQS, &data_size); 897 if (ret) 898 return ret; 899 900 if (data_size) { 901 data = memdup_user((void __user *)(arg + minsz), 902 data_size); 903 if (IS_ERR(data)) 904 return PTR_ERR(data); 905 } 906 907 mutex_lock(&vdev->igate); 908 909 ret = vfio_pci_set_irqs_ioctl(vdev, hdr.flags, hdr.index, 910 hdr.start, hdr.count, data); 911 912 mutex_unlock(&vdev->igate); 913 kfree(data); 914 915 return ret; 916 917 } else if (cmd == VFIO_DEVICE_RESET) { 918 int ret; 919 920 if (!vdev->reset_works) 921 return -EINVAL; 922 923 vfio_pci_zap_and_down_write_memory_lock(vdev); 924 ret = pci_try_reset_function(vdev->pdev); 925 up_write(&vdev->memory_lock); 926 927 return ret; 928 929 } else if (cmd == VFIO_DEVICE_GET_PCI_HOT_RESET_INFO) { 930 struct vfio_pci_hot_reset_info hdr; 931 struct vfio_pci_fill_info fill = { 0 }; 932 struct vfio_pci_dependent_device *devices = NULL; 933 bool slot = false; 934 int ret = 0; 935 936 minsz = offsetofend(struct vfio_pci_hot_reset_info, count); 937 938 if (copy_from_user(&hdr, (void __user *)arg, minsz)) 939 return -EFAULT; 940 941 if (hdr.argsz < minsz) 942 return -EINVAL; 943 944 hdr.flags = 0; 945 946 /* Can we do a slot or bus reset or neither? */ 947 if (!pci_probe_reset_slot(vdev->pdev->slot)) 948 slot = true; 949 else if (pci_probe_reset_bus(vdev->pdev->bus)) 950 return -ENODEV; 951 952 /* How many devices are affected? */ 953 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, 954 vfio_pci_count_devs, 955 &fill.max, slot); 956 if (ret) 957 return ret; 958 959 WARN_ON(!fill.max); /* Should always be at least one */ 960 961 /* 962 * If there's enough space, fill it now, otherwise return 963 * -ENOSPC and the number of devices affected. 964 */ 965 if (hdr.argsz < sizeof(hdr) + (fill.max * sizeof(*devices))) { 966 ret = -ENOSPC; 967 hdr.count = fill.max; 968 goto reset_info_exit; 969 } 970 971 devices = kcalloc(fill.max, sizeof(*devices), GFP_KERNEL); 972 if (!devices) 973 return -ENOMEM; 974 975 fill.devices = devices; 976 977 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, 978 vfio_pci_fill_devs, 979 &fill, slot); 980 981 /* 982 * If a device was removed between counting and filling, 983 * we may come up short of fill.max. If a device was 984 * added, we'll have a return of -EAGAIN above. 985 */ 986 if (!ret) 987 hdr.count = fill.cur; 988 989 reset_info_exit: 990 if (copy_to_user((void __user *)arg, &hdr, minsz)) 991 ret = -EFAULT; 992 993 if (!ret) { 994 if (copy_to_user((void __user *)(arg + minsz), devices, 995 hdr.count * sizeof(*devices))) 996 ret = -EFAULT; 997 } 998 999 kfree(devices); 1000 return ret; 1001 1002 } else if (cmd == VFIO_DEVICE_PCI_HOT_RESET) { 1003 struct vfio_pci_hot_reset hdr; 1004 int32_t *group_fds; 1005 struct vfio_group **groups; 1006 struct vfio_pci_group_info info; 1007 bool slot = false; 1008 int group_idx, count = 0, ret = 0; 1009 1010 minsz = offsetofend(struct vfio_pci_hot_reset, count); 1011 1012 if (copy_from_user(&hdr, (void __user *)arg, minsz)) 1013 return -EFAULT; 1014 1015 if (hdr.argsz < minsz || hdr.flags) 1016 return -EINVAL; 1017 1018 /* Can we do a slot or bus reset or neither? */ 1019 if (!pci_probe_reset_slot(vdev->pdev->slot)) 1020 slot = true; 1021 else if (pci_probe_reset_bus(vdev->pdev->bus)) 1022 return -ENODEV; 1023 1024 /* 1025 * We can't let userspace give us an arbitrarily large 1026 * buffer to copy, so verify how many we think there 1027 * could be. Note groups can have multiple devices so 1028 * one group per device is the max. 1029 */ 1030 ret = vfio_pci_for_each_slot_or_bus(vdev->pdev, 1031 vfio_pci_count_devs, 1032 &count, slot); 1033 if (ret) 1034 return ret; 1035 1036 /* Somewhere between 1 and count is OK */ 1037 if (!hdr.count || hdr.count > count) 1038 return -EINVAL; 1039 1040 group_fds = kcalloc(hdr.count, sizeof(*group_fds), GFP_KERNEL); 1041 groups = kcalloc(hdr.count, sizeof(*groups), GFP_KERNEL); 1042 if (!group_fds || !groups) { 1043 kfree(group_fds); 1044 kfree(groups); 1045 return -ENOMEM; 1046 } 1047 1048 if (copy_from_user(group_fds, (void __user *)(arg + minsz), 1049 hdr.count * sizeof(*group_fds))) { 1050 kfree(group_fds); 1051 kfree(groups); 1052 return -EFAULT; 1053 } 1054 1055 /* 1056 * For each group_fd, get the group through the vfio external 1057 * user interface and store the group and iommu ID. This 1058 * ensures the group is held across the reset. 1059 */ 1060 for (group_idx = 0; group_idx < hdr.count; group_idx++) { 1061 struct vfio_group *group; 1062 struct fd f = fdget(group_fds[group_idx]); 1063 if (!f.file) { 1064 ret = -EBADF; 1065 break; 1066 } 1067 1068 group = vfio_group_get_external_user(f.file); 1069 fdput(f); 1070 if (IS_ERR(group)) { 1071 ret = PTR_ERR(group); 1072 break; 1073 } 1074 1075 groups[group_idx] = group; 1076 } 1077 1078 kfree(group_fds); 1079 1080 /* release reference to groups on error */ 1081 if (ret) 1082 goto hot_reset_release; 1083 1084 info.count = hdr.count; 1085 info.groups = groups; 1086 1087 ret = vfio_pci_dev_set_hot_reset(vdev->vdev.dev_set, &info); 1088 1089 hot_reset_release: 1090 for (group_idx--; group_idx >= 0; group_idx--) 1091 vfio_group_put_external_user(groups[group_idx]); 1092 1093 kfree(groups); 1094 return ret; 1095 } else if (cmd == VFIO_DEVICE_IOEVENTFD) { 1096 struct vfio_device_ioeventfd ioeventfd; 1097 int count; 1098 1099 minsz = offsetofend(struct vfio_device_ioeventfd, fd); 1100 1101 if (copy_from_user(&ioeventfd, (void __user *)arg, minsz)) 1102 return -EFAULT; 1103 1104 if (ioeventfd.argsz < minsz) 1105 return -EINVAL; 1106 1107 if (ioeventfd.flags & ~VFIO_DEVICE_IOEVENTFD_SIZE_MASK) 1108 return -EINVAL; 1109 1110 count = ioeventfd.flags & VFIO_DEVICE_IOEVENTFD_SIZE_MASK; 1111 1112 if (hweight8(count) != 1 || ioeventfd.fd < -1) 1113 return -EINVAL; 1114 1115 return vfio_pci_ioeventfd(vdev, ioeventfd.offset, 1116 ioeventfd.data, count, ioeventfd.fd); 1117 } else if (cmd == VFIO_DEVICE_FEATURE) { 1118 struct vfio_device_feature feature; 1119 uuid_t uuid; 1120 1121 minsz = offsetofend(struct vfio_device_feature, flags); 1122 1123 if (copy_from_user(&feature, (void __user *)arg, minsz)) 1124 return -EFAULT; 1125 1126 if (feature.argsz < minsz) 1127 return -EINVAL; 1128 1129 /* Check unknown flags */ 1130 if (feature.flags & ~(VFIO_DEVICE_FEATURE_MASK | 1131 VFIO_DEVICE_FEATURE_SET | 1132 VFIO_DEVICE_FEATURE_GET | 1133 VFIO_DEVICE_FEATURE_PROBE)) 1134 return -EINVAL; 1135 1136 /* GET & SET are mutually exclusive except with PROBE */ 1137 if (!(feature.flags & VFIO_DEVICE_FEATURE_PROBE) && 1138 (feature.flags & VFIO_DEVICE_FEATURE_SET) && 1139 (feature.flags & VFIO_DEVICE_FEATURE_GET)) 1140 return -EINVAL; 1141 1142 switch (feature.flags & VFIO_DEVICE_FEATURE_MASK) { 1143 case VFIO_DEVICE_FEATURE_PCI_VF_TOKEN: 1144 if (!vdev->vf_token) 1145 return -ENOTTY; 1146 1147 /* 1148 * We do not support GET of the VF Token UUID as this 1149 * could expose the token of the previous device user. 1150 */ 1151 if (feature.flags & VFIO_DEVICE_FEATURE_GET) 1152 return -EINVAL; 1153 1154 if (feature.flags & VFIO_DEVICE_FEATURE_PROBE) 1155 return 0; 1156 1157 /* Don't SET unless told to do so */ 1158 if (!(feature.flags & VFIO_DEVICE_FEATURE_SET)) 1159 return -EINVAL; 1160 1161 if (feature.argsz < minsz + sizeof(uuid)) 1162 return -EINVAL; 1163 1164 if (copy_from_user(&uuid, (void __user *)(arg + minsz), 1165 sizeof(uuid))) 1166 return -EFAULT; 1167 1168 mutex_lock(&vdev->vf_token->lock); 1169 uuid_copy(&vdev->vf_token->uuid, &uuid); 1170 mutex_unlock(&vdev->vf_token->lock); 1171 1172 return 0; 1173 default: 1174 return -ENOTTY; 1175 } 1176 } 1177 1178 return -ENOTTY; 1179 } 1180 EXPORT_SYMBOL_GPL(vfio_pci_core_ioctl); 1181 1182 static ssize_t vfio_pci_rw(struct vfio_pci_core_device *vdev, char __user *buf, 1183 size_t count, loff_t *ppos, bool iswrite) 1184 { 1185 unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); 1186 1187 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions) 1188 return -EINVAL; 1189 1190 switch (index) { 1191 case VFIO_PCI_CONFIG_REGION_INDEX: 1192 return vfio_pci_config_rw(vdev, buf, count, ppos, iswrite); 1193 1194 case VFIO_PCI_ROM_REGION_INDEX: 1195 if (iswrite) 1196 return -EINVAL; 1197 return vfio_pci_bar_rw(vdev, buf, count, ppos, false); 1198 1199 case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX: 1200 return vfio_pci_bar_rw(vdev, buf, count, ppos, iswrite); 1201 1202 case VFIO_PCI_VGA_REGION_INDEX: 1203 return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite); 1204 default: 1205 index -= VFIO_PCI_NUM_REGIONS; 1206 return vdev->region[index].ops->rw(vdev, buf, 1207 count, ppos, iswrite); 1208 } 1209 1210 return -EINVAL; 1211 } 1212 1213 ssize_t vfio_pci_core_read(struct vfio_device *core_vdev, char __user *buf, 1214 size_t count, loff_t *ppos) 1215 { 1216 struct vfio_pci_core_device *vdev = 1217 container_of(core_vdev, struct vfio_pci_core_device, vdev); 1218 1219 if (!count) 1220 return 0; 1221 1222 return vfio_pci_rw(vdev, buf, count, ppos, false); 1223 } 1224 EXPORT_SYMBOL_GPL(vfio_pci_core_read); 1225 1226 ssize_t vfio_pci_core_write(struct vfio_device *core_vdev, const char __user *buf, 1227 size_t count, loff_t *ppos) 1228 { 1229 struct vfio_pci_core_device *vdev = 1230 container_of(core_vdev, struct vfio_pci_core_device, vdev); 1231 1232 if (!count) 1233 return 0; 1234 1235 return vfio_pci_rw(vdev, (char __user *)buf, count, ppos, true); 1236 } 1237 EXPORT_SYMBOL_GPL(vfio_pci_core_write); 1238 1239 /* Return 1 on zap and vma_lock acquired, 0 on contention (only with @try) */ 1240 static int vfio_pci_zap_and_vma_lock(struct vfio_pci_core_device *vdev, bool try) 1241 { 1242 struct vfio_pci_mmap_vma *mmap_vma, *tmp; 1243 1244 /* 1245 * Lock ordering: 1246 * vma_lock is nested under mmap_lock for vm_ops callback paths. 1247 * The memory_lock semaphore is used by both code paths calling 1248 * into this function to zap vmas and the vm_ops.fault callback 1249 * to protect the memory enable state of the device. 1250 * 1251 * When zapping vmas we need to maintain the mmap_lock => vma_lock 1252 * ordering, which requires using vma_lock to walk vma_list to 1253 * acquire an mm, then dropping vma_lock to get the mmap_lock and 1254 * reacquiring vma_lock. This logic is derived from similar 1255 * requirements in uverbs_user_mmap_disassociate(). 1256 * 1257 * mmap_lock must always be the top-level lock when it is taken. 1258 * Therefore we can only hold the memory_lock write lock when 1259 * vma_list is empty, as we'd need to take mmap_lock to clear 1260 * entries. vma_list can only be guaranteed empty when holding 1261 * vma_lock, thus memory_lock is nested under vma_lock. 1262 * 1263 * This enables the vm_ops.fault callback to acquire vma_lock, 1264 * followed by memory_lock read lock, while already holding 1265 * mmap_lock without risk of deadlock. 1266 */ 1267 while (1) { 1268 struct mm_struct *mm = NULL; 1269 1270 if (try) { 1271 if (!mutex_trylock(&vdev->vma_lock)) 1272 return 0; 1273 } else { 1274 mutex_lock(&vdev->vma_lock); 1275 } 1276 while (!list_empty(&vdev->vma_list)) { 1277 mmap_vma = list_first_entry(&vdev->vma_list, 1278 struct vfio_pci_mmap_vma, 1279 vma_next); 1280 mm = mmap_vma->vma->vm_mm; 1281 if (mmget_not_zero(mm)) 1282 break; 1283 1284 list_del(&mmap_vma->vma_next); 1285 kfree(mmap_vma); 1286 mm = NULL; 1287 } 1288 if (!mm) 1289 return 1; 1290 mutex_unlock(&vdev->vma_lock); 1291 1292 if (try) { 1293 if (!mmap_read_trylock(mm)) { 1294 mmput(mm); 1295 return 0; 1296 } 1297 } else { 1298 mmap_read_lock(mm); 1299 } 1300 if (try) { 1301 if (!mutex_trylock(&vdev->vma_lock)) { 1302 mmap_read_unlock(mm); 1303 mmput(mm); 1304 return 0; 1305 } 1306 } else { 1307 mutex_lock(&vdev->vma_lock); 1308 } 1309 list_for_each_entry_safe(mmap_vma, tmp, 1310 &vdev->vma_list, vma_next) { 1311 struct vm_area_struct *vma = mmap_vma->vma; 1312 1313 if (vma->vm_mm != mm) 1314 continue; 1315 1316 list_del(&mmap_vma->vma_next); 1317 kfree(mmap_vma); 1318 1319 zap_vma_ptes(vma, vma->vm_start, 1320 vma->vm_end - vma->vm_start); 1321 } 1322 mutex_unlock(&vdev->vma_lock); 1323 mmap_read_unlock(mm); 1324 mmput(mm); 1325 } 1326 } 1327 1328 void vfio_pci_zap_and_down_write_memory_lock(struct vfio_pci_core_device *vdev) 1329 { 1330 vfio_pci_zap_and_vma_lock(vdev, false); 1331 down_write(&vdev->memory_lock); 1332 mutex_unlock(&vdev->vma_lock); 1333 } 1334 1335 u16 vfio_pci_memory_lock_and_enable(struct vfio_pci_core_device *vdev) 1336 { 1337 u16 cmd; 1338 1339 down_write(&vdev->memory_lock); 1340 pci_read_config_word(vdev->pdev, PCI_COMMAND, &cmd); 1341 if (!(cmd & PCI_COMMAND_MEMORY)) 1342 pci_write_config_word(vdev->pdev, PCI_COMMAND, 1343 cmd | PCI_COMMAND_MEMORY); 1344 1345 return cmd; 1346 } 1347 1348 void vfio_pci_memory_unlock_and_restore(struct vfio_pci_core_device *vdev, u16 cmd) 1349 { 1350 pci_write_config_word(vdev->pdev, PCI_COMMAND, cmd); 1351 up_write(&vdev->memory_lock); 1352 } 1353 1354 /* Caller holds vma_lock */ 1355 static int __vfio_pci_add_vma(struct vfio_pci_core_device *vdev, 1356 struct vm_area_struct *vma) 1357 { 1358 struct vfio_pci_mmap_vma *mmap_vma; 1359 1360 mmap_vma = kmalloc(sizeof(*mmap_vma), GFP_KERNEL); 1361 if (!mmap_vma) 1362 return -ENOMEM; 1363 1364 mmap_vma->vma = vma; 1365 list_add(&mmap_vma->vma_next, &vdev->vma_list); 1366 1367 return 0; 1368 } 1369 1370 /* 1371 * Zap mmaps on open so that we can fault them in on access and therefore 1372 * our vma_list only tracks mappings accessed since last zap. 1373 */ 1374 static void vfio_pci_mmap_open(struct vm_area_struct *vma) 1375 { 1376 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start); 1377 } 1378 1379 static void vfio_pci_mmap_close(struct vm_area_struct *vma) 1380 { 1381 struct vfio_pci_core_device *vdev = vma->vm_private_data; 1382 struct vfio_pci_mmap_vma *mmap_vma; 1383 1384 mutex_lock(&vdev->vma_lock); 1385 list_for_each_entry(mmap_vma, &vdev->vma_list, vma_next) { 1386 if (mmap_vma->vma == vma) { 1387 list_del(&mmap_vma->vma_next); 1388 kfree(mmap_vma); 1389 break; 1390 } 1391 } 1392 mutex_unlock(&vdev->vma_lock); 1393 } 1394 1395 static vm_fault_t vfio_pci_mmap_fault(struct vm_fault *vmf) 1396 { 1397 struct vm_area_struct *vma = vmf->vma; 1398 struct vfio_pci_core_device *vdev = vma->vm_private_data; 1399 struct vfio_pci_mmap_vma *mmap_vma; 1400 vm_fault_t ret = VM_FAULT_NOPAGE; 1401 1402 mutex_lock(&vdev->vma_lock); 1403 down_read(&vdev->memory_lock); 1404 1405 if (!__vfio_pci_memory_enabled(vdev)) { 1406 ret = VM_FAULT_SIGBUS; 1407 goto up_out; 1408 } 1409 1410 /* 1411 * We populate the whole vma on fault, so we need to test whether 1412 * the vma has already been mapped, such as for concurrent faults 1413 * to the same vma. io_remap_pfn_range() will trigger a BUG_ON if 1414 * we ask it to fill the same range again. 1415 */ 1416 list_for_each_entry(mmap_vma, &vdev->vma_list, vma_next) { 1417 if (mmap_vma->vma == vma) 1418 goto up_out; 1419 } 1420 1421 if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, 1422 vma->vm_end - vma->vm_start, 1423 vma->vm_page_prot)) { 1424 ret = VM_FAULT_SIGBUS; 1425 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start); 1426 goto up_out; 1427 } 1428 1429 if (__vfio_pci_add_vma(vdev, vma)) { 1430 ret = VM_FAULT_OOM; 1431 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start); 1432 } 1433 1434 up_out: 1435 up_read(&vdev->memory_lock); 1436 mutex_unlock(&vdev->vma_lock); 1437 return ret; 1438 } 1439 1440 static const struct vm_operations_struct vfio_pci_mmap_ops = { 1441 .open = vfio_pci_mmap_open, 1442 .close = vfio_pci_mmap_close, 1443 .fault = vfio_pci_mmap_fault, 1444 }; 1445 1446 int vfio_pci_core_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma) 1447 { 1448 struct vfio_pci_core_device *vdev = 1449 container_of(core_vdev, struct vfio_pci_core_device, vdev); 1450 struct pci_dev *pdev = vdev->pdev; 1451 unsigned int index; 1452 u64 phys_len, req_len, pgoff, req_start; 1453 int ret; 1454 1455 index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT); 1456 1457 if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions) 1458 return -EINVAL; 1459 if (vma->vm_end < vma->vm_start) 1460 return -EINVAL; 1461 if ((vma->vm_flags & VM_SHARED) == 0) 1462 return -EINVAL; 1463 if (index >= VFIO_PCI_NUM_REGIONS) { 1464 int regnum = index - VFIO_PCI_NUM_REGIONS; 1465 struct vfio_pci_region *region = vdev->region + regnum; 1466 1467 if (region->ops && region->ops->mmap && 1468 (region->flags & VFIO_REGION_INFO_FLAG_MMAP)) 1469 return region->ops->mmap(vdev, region, vma); 1470 return -EINVAL; 1471 } 1472 if (index >= VFIO_PCI_ROM_REGION_INDEX) 1473 return -EINVAL; 1474 if (!vdev->bar_mmap_supported[index]) 1475 return -EINVAL; 1476 1477 phys_len = PAGE_ALIGN(pci_resource_len(pdev, index)); 1478 req_len = vma->vm_end - vma->vm_start; 1479 pgoff = vma->vm_pgoff & 1480 ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1); 1481 req_start = pgoff << PAGE_SHIFT; 1482 1483 if (req_start + req_len > phys_len) 1484 return -EINVAL; 1485 1486 /* 1487 * Even though we don't make use of the barmap for the mmap, 1488 * we need to request the region and the barmap tracks that. 1489 */ 1490 if (!vdev->barmap[index]) { 1491 ret = pci_request_selected_regions(pdev, 1492 1 << index, "vfio-pci"); 1493 if (ret) 1494 return ret; 1495 1496 vdev->barmap[index] = pci_iomap(pdev, index, 0); 1497 if (!vdev->barmap[index]) { 1498 pci_release_selected_regions(pdev, 1 << index); 1499 return -ENOMEM; 1500 } 1501 } 1502 1503 vma->vm_private_data = vdev; 1504 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 1505 vma->vm_pgoff = (pci_resource_start(pdev, index) >> PAGE_SHIFT) + pgoff; 1506 1507 /* 1508 * See remap_pfn_range(), called from vfio_pci_fault() but we can't 1509 * change vm_flags within the fault handler. Set them now. 1510 */ 1511 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; 1512 vma->vm_ops = &vfio_pci_mmap_ops; 1513 1514 return 0; 1515 } 1516 EXPORT_SYMBOL_GPL(vfio_pci_core_mmap); 1517 1518 void vfio_pci_core_request(struct vfio_device *core_vdev, unsigned int count) 1519 { 1520 struct vfio_pci_core_device *vdev = 1521 container_of(core_vdev, struct vfio_pci_core_device, vdev); 1522 struct pci_dev *pdev = vdev->pdev; 1523 1524 mutex_lock(&vdev->igate); 1525 1526 if (vdev->req_trigger) { 1527 if (!(count % 10)) 1528 pci_notice_ratelimited(pdev, 1529 "Relaying device request to user (#%u)\n", 1530 count); 1531 eventfd_signal(vdev->req_trigger, 1); 1532 } else if (count == 0) { 1533 pci_warn(pdev, 1534 "No device request channel registered, blocked until released by user\n"); 1535 } 1536 1537 mutex_unlock(&vdev->igate); 1538 } 1539 EXPORT_SYMBOL_GPL(vfio_pci_core_request); 1540 1541 static int vfio_pci_validate_vf_token(struct vfio_pci_core_device *vdev, 1542 bool vf_token, uuid_t *uuid) 1543 { 1544 /* 1545 * There's always some degree of trust or collaboration between SR-IOV 1546 * PF and VFs, even if just that the PF hosts the SR-IOV capability and 1547 * can disrupt VFs with a reset, but often the PF has more explicit 1548 * access to deny service to the VF or access data passed through the 1549 * VF. We therefore require an opt-in via a shared VF token (UUID) to 1550 * represent this trust. This both prevents that a VF driver might 1551 * assume the PF driver is a trusted, in-kernel driver, and also that 1552 * a PF driver might be replaced with a rogue driver, unknown to in-use 1553 * VF drivers. 1554 * 1555 * Therefore when presented with a VF, if the PF is a vfio device and 1556 * it is bound to the vfio-pci driver, the user needs to provide a VF 1557 * token to access the device, in the form of appending a vf_token to 1558 * the device name, for example: 1559 * 1560 * "0000:04:10.0 vf_token=bd8d9d2b-5a5f-4f5a-a211-f591514ba1f3" 1561 * 1562 * When presented with a PF which has VFs in use, the user must also 1563 * provide the current VF token to prove collaboration with existing 1564 * VF users. If VFs are not in use, the VF token provided for the PF 1565 * device will act to set the VF token. 1566 * 1567 * If the VF token is provided but unused, an error is generated. 1568 */ 1569 if (!vdev->pdev->is_virtfn && !vdev->vf_token && !vf_token) 1570 return 0; /* No VF token provided or required */ 1571 1572 if (vdev->pdev->is_virtfn) { 1573 struct vfio_pci_core_device *pf_vdev = get_pf_vdev(vdev); 1574 bool match; 1575 1576 if (!pf_vdev) { 1577 if (!vf_token) 1578 return 0; /* PF is not vfio-pci, no VF token */ 1579 1580 pci_info_ratelimited(vdev->pdev, 1581 "VF token incorrectly provided, PF not bound to vfio-pci\n"); 1582 return -EINVAL; 1583 } 1584 1585 if (!vf_token) { 1586 vfio_device_put(&pf_vdev->vdev); 1587 pci_info_ratelimited(vdev->pdev, 1588 "VF token required to access device\n"); 1589 return -EACCES; 1590 } 1591 1592 mutex_lock(&pf_vdev->vf_token->lock); 1593 match = uuid_equal(uuid, &pf_vdev->vf_token->uuid); 1594 mutex_unlock(&pf_vdev->vf_token->lock); 1595 1596 vfio_device_put(&pf_vdev->vdev); 1597 1598 if (!match) { 1599 pci_info_ratelimited(vdev->pdev, 1600 "Incorrect VF token provided for device\n"); 1601 return -EACCES; 1602 } 1603 } else if (vdev->vf_token) { 1604 mutex_lock(&vdev->vf_token->lock); 1605 if (vdev->vf_token->users) { 1606 if (!vf_token) { 1607 mutex_unlock(&vdev->vf_token->lock); 1608 pci_info_ratelimited(vdev->pdev, 1609 "VF token required to access device\n"); 1610 return -EACCES; 1611 } 1612 1613 if (!uuid_equal(uuid, &vdev->vf_token->uuid)) { 1614 mutex_unlock(&vdev->vf_token->lock); 1615 pci_info_ratelimited(vdev->pdev, 1616 "Incorrect VF token provided for device\n"); 1617 return -EACCES; 1618 } 1619 } else if (vf_token) { 1620 uuid_copy(&vdev->vf_token->uuid, uuid); 1621 } 1622 1623 mutex_unlock(&vdev->vf_token->lock); 1624 } else if (vf_token) { 1625 pci_info_ratelimited(vdev->pdev, 1626 "VF token incorrectly provided, not a PF or VF\n"); 1627 return -EINVAL; 1628 } 1629 1630 return 0; 1631 } 1632 1633 #define VF_TOKEN_ARG "vf_token=" 1634 1635 int vfio_pci_core_match(struct vfio_device *core_vdev, char *buf) 1636 { 1637 struct vfio_pci_core_device *vdev = 1638 container_of(core_vdev, struct vfio_pci_core_device, vdev); 1639 bool vf_token = false; 1640 uuid_t uuid; 1641 int ret; 1642 1643 if (strncmp(pci_name(vdev->pdev), buf, strlen(pci_name(vdev->pdev)))) 1644 return 0; /* No match */ 1645 1646 if (strlen(buf) > strlen(pci_name(vdev->pdev))) { 1647 buf += strlen(pci_name(vdev->pdev)); 1648 1649 if (*buf != ' ') 1650 return 0; /* No match: non-whitespace after name */ 1651 1652 while (*buf) { 1653 if (*buf == ' ') { 1654 buf++; 1655 continue; 1656 } 1657 1658 if (!vf_token && !strncmp(buf, VF_TOKEN_ARG, 1659 strlen(VF_TOKEN_ARG))) { 1660 buf += strlen(VF_TOKEN_ARG); 1661 1662 if (strlen(buf) < UUID_STRING_LEN) 1663 return -EINVAL; 1664 1665 ret = uuid_parse(buf, &uuid); 1666 if (ret) 1667 return ret; 1668 1669 vf_token = true; 1670 buf += UUID_STRING_LEN; 1671 } else { 1672 /* Unknown/duplicate option */ 1673 return -EINVAL; 1674 } 1675 } 1676 } 1677 1678 ret = vfio_pci_validate_vf_token(vdev, vf_token, &uuid); 1679 if (ret) 1680 return ret; 1681 1682 return 1; /* Match */ 1683 } 1684 EXPORT_SYMBOL_GPL(vfio_pci_core_match); 1685 1686 static int vfio_pci_bus_notifier(struct notifier_block *nb, 1687 unsigned long action, void *data) 1688 { 1689 struct vfio_pci_core_device *vdev = container_of(nb, 1690 struct vfio_pci_core_device, nb); 1691 struct device *dev = data; 1692 struct pci_dev *pdev = to_pci_dev(dev); 1693 struct pci_dev *physfn = pci_physfn(pdev); 1694 1695 if (action == BUS_NOTIFY_ADD_DEVICE && 1696 pdev->is_virtfn && physfn == vdev->pdev) { 1697 pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n", 1698 pci_name(pdev)); 1699 pdev->driver_override = kasprintf(GFP_KERNEL, "%s", 1700 vdev->vdev.ops->name); 1701 } else if (action == BUS_NOTIFY_BOUND_DRIVER && 1702 pdev->is_virtfn && physfn == vdev->pdev) { 1703 struct pci_driver *drv = pci_dev_driver(pdev); 1704 1705 if (drv && drv != pci_dev_driver(vdev->pdev)) 1706 pci_warn(vdev->pdev, 1707 "VF %s bound to driver %s while PF bound to driver %s\n", 1708 pci_name(pdev), drv->name, 1709 pci_dev_driver(vdev->pdev)->name); 1710 } 1711 1712 return 0; 1713 } 1714 1715 static int vfio_pci_vf_init(struct vfio_pci_core_device *vdev) 1716 { 1717 struct pci_dev *pdev = vdev->pdev; 1718 int ret; 1719 1720 if (!pdev->is_physfn) 1721 return 0; 1722 1723 vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL); 1724 if (!vdev->vf_token) 1725 return -ENOMEM; 1726 1727 mutex_init(&vdev->vf_token->lock); 1728 uuid_gen(&vdev->vf_token->uuid); 1729 1730 vdev->nb.notifier_call = vfio_pci_bus_notifier; 1731 ret = bus_register_notifier(&pci_bus_type, &vdev->nb); 1732 if (ret) { 1733 kfree(vdev->vf_token); 1734 return ret; 1735 } 1736 return 0; 1737 } 1738 1739 static void vfio_pci_vf_uninit(struct vfio_pci_core_device *vdev) 1740 { 1741 if (!vdev->vf_token) 1742 return; 1743 1744 bus_unregister_notifier(&pci_bus_type, &vdev->nb); 1745 WARN_ON(vdev->vf_token->users); 1746 mutex_destroy(&vdev->vf_token->lock); 1747 kfree(vdev->vf_token); 1748 } 1749 1750 static int vfio_pci_vga_init(struct vfio_pci_core_device *vdev) 1751 { 1752 struct pci_dev *pdev = vdev->pdev; 1753 int ret; 1754 1755 if (!vfio_pci_is_vga(pdev)) 1756 return 0; 1757 1758 ret = vga_client_register(pdev, vfio_pci_set_decode); 1759 if (ret) 1760 return ret; 1761 vga_set_legacy_decoding(pdev, vfio_pci_set_decode(pdev, false)); 1762 return 0; 1763 } 1764 1765 static void vfio_pci_vga_uninit(struct vfio_pci_core_device *vdev) 1766 { 1767 struct pci_dev *pdev = vdev->pdev; 1768 1769 if (!vfio_pci_is_vga(pdev)) 1770 return; 1771 vga_client_unregister(pdev); 1772 vga_set_legacy_decoding(pdev, VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM | 1773 VGA_RSRC_LEGACY_IO | 1774 VGA_RSRC_LEGACY_MEM); 1775 } 1776 1777 void vfio_pci_core_init_device(struct vfio_pci_core_device *vdev, 1778 struct pci_dev *pdev, 1779 const struct vfio_device_ops *vfio_pci_ops) 1780 { 1781 vfio_init_group_dev(&vdev->vdev, &pdev->dev, vfio_pci_ops); 1782 vdev->pdev = pdev; 1783 vdev->irq_type = VFIO_PCI_NUM_IRQS; 1784 mutex_init(&vdev->igate); 1785 spin_lock_init(&vdev->irqlock); 1786 mutex_init(&vdev->ioeventfds_lock); 1787 INIT_LIST_HEAD(&vdev->dummy_resources_list); 1788 INIT_LIST_HEAD(&vdev->ioeventfds_list); 1789 mutex_init(&vdev->vma_lock); 1790 INIT_LIST_HEAD(&vdev->vma_list); 1791 init_rwsem(&vdev->memory_lock); 1792 } 1793 EXPORT_SYMBOL_GPL(vfio_pci_core_init_device); 1794 1795 void vfio_pci_core_uninit_device(struct vfio_pci_core_device *vdev) 1796 { 1797 mutex_destroy(&vdev->igate); 1798 mutex_destroy(&vdev->ioeventfds_lock); 1799 mutex_destroy(&vdev->vma_lock); 1800 vfio_uninit_group_dev(&vdev->vdev); 1801 kfree(vdev->region); 1802 kfree(vdev->pm_save); 1803 } 1804 EXPORT_SYMBOL_GPL(vfio_pci_core_uninit_device); 1805 1806 int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev) 1807 { 1808 struct pci_dev *pdev = vdev->pdev; 1809 int ret; 1810 1811 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL) 1812 return -EINVAL; 1813 1814 /* 1815 * Prevent binding to PFs with VFs enabled, the VFs might be in use 1816 * by the host or other users. We cannot capture the VFs if they 1817 * already exist, nor can we track VF users. Disabling SR-IOV here 1818 * would initiate removing the VFs, which would unbind the driver, 1819 * which is prone to blocking if that VF is also in use by vfio-pci. 1820 * Just reject these PFs and let the user sort it out. 1821 */ 1822 if (pci_num_vf(pdev)) { 1823 pci_warn(pdev, "Cannot bind to PF with SR-IOV enabled\n"); 1824 return -EBUSY; 1825 } 1826 1827 if (pci_is_root_bus(pdev->bus)) { 1828 ret = vfio_assign_device_set(&vdev->vdev, vdev); 1829 } else if (!pci_probe_reset_slot(pdev->slot)) { 1830 ret = vfio_assign_device_set(&vdev->vdev, pdev->slot); 1831 } else { 1832 /* 1833 * If there is no slot reset support for this device, the whole 1834 * bus needs to be grouped together to support bus-wide resets. 1835 */ 1836 ret = vfio_assign_device_set(&vdev->vdev, pdev->bus); 1837 } 1838 1839 if (ret) 1840 return ret; 1841 ret = vfio_pci_vf_init(vdev); 1842 if (ret) 1843 return ret; 1844 ret = vfio_pci_vga_init(vdev); 1845 if (ret) 1846 goto out_vf; 1847 1848 vfio_pci_probe_power_state(vdev); 1849 1850 if (!disable_idle_d3) { 1851 /* 1852 * pci-core sets the device power state to an unknown value at 1853 * bootup and after being removed from a driver. The only 1854 * transition it allows from this unknown state is to D0, which 1855 * typically happens when a driver calls pci_enable_device(). 1856 * We're not ready to enable the device yet, but we do want to 1857 * be able to get to D3. Therefore first do a D0 transition 1858 * before going to D3. 1859 */ 1860 vfio_pci_set_power_state(vdev, PCI_D0); 1861 vfio_pci_set_power_state(vdev, PCI_D3hot); 1862 } 1863 1864 ret = vfio_register_group_dev(&vdev->vdev); 1865 if (ret) 1866 goto out_power; 1867 return 0; 1868 1869 out_power: 1870 if (!disable_idle_d3) 1871 vfio_pci_set_power_state(vdev, PCI_D0); 1872 out_vf: 1873 vfio_pci_vf_uninit(vdev); 1874 return ret; 1875 } 1876 EXPORT_SYMBOL_GPL(vfio_pci_core_register_device); 1877 1878 void vfio_pci_core_unregister_device(struct vfio_pci_core_device *vdev) 1879 { 1880 struct pci_dev *pdev = vdev->pdev; 1881 1882 pci_disable_sriov(pdev); 1883 1884 vfio_unregister_group_dev(&vdev->vdev); 1885 1886 vfio_pci_vf_uninit(vdev); 1887 vfio_pci_vga_uninit(vdev); 1888 1889 if (!disable_idle_d3) 1890 vfio_pci_set_power_state(vdev, PCI_D0); 1891 } 1892 EXPORT_SYMBOL_GPL(vfio_pci_core_unregister_device); 1893 1894 static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, 1895 pci_channel_state_t state) 1896 { 1897 struct vfio_pci_core_device *vdev; 1898 struct vfio_device *device; 1899 1900 device = vfio_device_get_from_dev(&pdev->dev); 1901 if (device == NULL) 1902 return PCI_ERS_RESULT_DISCONNECT; 1903 1904 vdev = container_of(device, struct vfio_pci_core_device, vdev); 1905 1906 mutex_lock(&vdev->igate); 1907 1908 if (vdev->err_trigger) 1909 eventfd_signal(vdev->err_trigger, 1); 1910 1911 mutex_unlock(&vdev->igate); 1912 1913 vfio_device_put(device); 1914 1915 return PCI_ERS_RESULT_CAN_RECOVER; 1916 } 1917 1918 int vfio_pci_core_sriov_configure(struct pci_dev *pdev, int nr_virtfn) 1919 { 1920 struct vfio_device *device; 1921 int ret = 0; 1922 1923 device = vfio_device_get_from_dev(&pdev->dev); 1924 if (!device) 1925 return -ENODEV; 1926 1927 if (nr_virtfn == 0) 1928 pci_disable_sriov(pdev); 1929 else 1930 ret = pci_enable_sriov(pdev, nr_virtfn); 1931 1932 vfio_device_put(device); 1933 1934 return ret < 0 ? ret : nr_virtfn; 1935 } 1936 EXPORT_SYMBOL_GPL(vfio_pci_core_sriov_configure); 1937 1938 const struct pci_error_handlers vfio_pci_core_err_handlers = { 1939 .error_detected = vfio_pci_aer_err_detected, 1940 }; 1941 EXPORT_SYMBOL_GPL(vfio_pci_core_err_handlers); 1942 1943 static bool vfio_dev_in_groups(struct vfio_pci_core_device *vdev, 1944 struct vfio_pci_group_info *groups) 1945 { 1946 unsigned int i; 1947 1948 for (i = 0; i < groups->count; i++) 1949 if (groups->groups[i] == vdev->vdev.group) 1950 return true; 1951 return false; 1952 } 1953 1954 static int vfio_pci_is_device_in_set(struct pci_dev *pdev, void *data) 1955 { 1956 struct vfio_device_set *dev_set = data; 1957 struct vfio_device *cur; 1958 1959 list_for_each_entry(cur, &dev_set->device_list, dev_set_list) 1960 if (cur->dev == &pdev->dev) 1961 return 0; 1962 return -EBUSY; 1963 } 1964 1965 /* 1966 * vfio-core considers a group to be viable and will create a vfio_device even 1967 * if some devices are bound to drivers like pci-stub or pcieport. Here we 1968 * require all PCI devices to be inside our dev_set since that ensures they stay 1969 * put and that every driver controlling the device can co-ordinate with the 1970 * device reset. 1971 * 1972 * Returns the pci_dev to pass to pci_reset_bus() if every PCI device to be 1973 * reset is inside the dev_set, and pci_reset_bus() can succeed. NULL otherwise. 1974 */ 1975 static struct pci_dev * 1976 vfio_pci_dev_set_resettable(struct vfio_device_set *dev_set) 1977 { 1978 struct pci_dev *pdev; 1979 1980 lockdep_assert_held(&dev_set->lock); 1981 1982 /* 1983 * By definition all PCI devices in the dev_set share the same PCI 1984 * reset, so any pci_dev will have the same outcomes for 1985 * pci_probe_reset_*() and pci_reset_bus(). 1986 */ 1987 pdev = list_first_entry(&dev_set->device_list, 1988 struct vfio_pci_core_device, 1989 vdev.dev_set_list)->pdev; 1990 1991 /* pci_reset_bus() is supported */ 1992 if (pci_probe_reset_slot(pdev->slot) && pci_probe_reset_bus(pdev->bus)) 1993 return NULL; 1994 1995 if (vfio_pci_for_each_slot_or_bus(pdev, vfio_pci_is_device_in_set, 1996 dev_set, 1997 !pci_probe_reset_slot(pdev->slot))) 1998 return NULL; 1999 return pdev; 2000 } 2001 2002 /* 2003 * We need to get memory_lock for each device, but devices can share mmap_lock, 2004 * therefore we need to zap and hold the vma_lock for each device, and only then 2005 * get each memory_lock. 2006 */ 2007 static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, 2008 struct vfio_pci_group_info *groups) 2009 { 2010 struct vfio_pci_core_device *cur_mem; 2011 struct vfio_pci_core_device *cur_vma; 2012 struct vfio_pci_core_device *cur; 2013 struct pci_dev *pdev; 2014 bool is_mem = true; 2015 int ret; 2016 2017 mutex_lock(&dev_set->lock); 2018 cur_mem = list_first_entry(&dev_set->device_list, 2019 struct vfio_pci_core_device, 2020 vdev.dev_set_list); 2021 2022 pdev = vfio_pci_dev_set_resettable(dev_set); 2023 if (!pdev) { 2024 ret = -EINVAL; 2025 goto err_unlock; 2026 } 2027 2028 list_for_each_entry(cur_vma, &dev_set->device_list, vdev.dev_set_list) { 2029 /* 2030 * Test whether all the affected devices are contained by the 2031 * set of groups provided by the user. 2032 */ 2033 if (!vfio_dev_in_groups(cur_vma, groups)) { 2034 ret = -EINVAL; 2035 goto err_undo; 2036 } 2037 2038 /* 2039 * Locking multiple devices is prone to deadlock, runaway and 2040 * unwind if we hit contention. 2041 */ 2042 if (!vfio_pci_zap_and_vma_lock(cur_vma, true)) { 2043 ret = -EBUSY; 2044 goto err_undo; 2045 } 2046 } 2047 cur_vma = NULL; 2048 2049 list_for_each_entry(cur_mem, &dev_set->device_list, vdev.dev_set_list) { 2050 if (!down_write_trylock(&cur_mem->memory_lock)) { 2051 ret = -EBUSY; 2052 goto err_undo; 2053 } 2054 mutex_unlock(&cur_mem->vma_lock); 2055 } 2056 cur_mem = NULL; 2057 2058 ret = pci_reset_bus(pdev); 2059 2060 err_undo: 2061 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) { 2062 if (cur == cur_mem) 2063 is_mem = false; 2064 if (cur == cur_vma) 2065 break; 2066 if (is_mem) 2067 up_write(&cur->memory_lock); 2068 else 2069 mutex_unlock(&cur->vma_lock); 2070 } 2071 err_unlock: 2072 mutex_unlock(&dev_set->lock); 2073 return ret; 2074 } 2075 2076 static bool vfio_pci_dev_set_needs_reset(struct vfio_device_set *dev_set) 2077 { 2078 struct vfio_pci_core_device *cur; 2079 bool needs_reset = false; 2080 2081 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) { 2082 /* No VFIO device in the set can have an open device FD */ 2083 if (cur->vdev.open_count) 2084 return false; 2085 needs_reset |= cur->needs_reset; 2086 } 2087 return needs_reset; 2088 } 2089 2090 /* 2091 * If a bus or slot reset is available for the provided dev_set and: 2092 * - All of the devices affected by that bus or slot reset are unused 2093 * - At least one of the affected devices is marked dirty via 2094 * needs_reset (such as by lack of FLR support) 2095 * Then attempt to perform that bus or slot reset. 2096 * Returns true if the dev_set was reset. 2097 */ 2098 static bool vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set) 2099 { 2100 struct vfio_pci_core_device *cur; 2101 struct pci_dev *pdev; 2102 int ret; 2103 2104 if (!vfio_pci_dev_set_needs_reset(dev_set)) 2105 return false; 2106 2107 pdev = vfio_pci_dev_set_resettable(dev_set); 2108 if (!pdev) 2109 return false; 2110 2111 ret = pci_reset_bus(pdev); 2112 if (ret) 2113 return false; 2114 2115 list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) { 2116 cur->needs_reset = false; 2117 if (!disable_idle_d3) 2118 vfio_pci_set_power_state(cur, PCI_D3hot); 2119 } 2120 return true; 2121 } 2122 2123 void vfio_pci_core_set_params(bool is_nointxmask, bool is_disable_vga, 2124 bool is_disable_idle_d3) 2125 { 2126 nointxmask = is_nointxmask; 2127 disable_vga = is_disable_vga; 2128 disable_idle_d3 = is_disable_idle_d3; 2129 } 2130 EXPORT_SYMBOL_GPL(vfio_pci_core_set_params); 2131 2132 static void vfio_pci_core_cleanup(void) 2133 { 2134 vfio_pci_uninit_perm_bits(); 2135 } 2136 2137 static int __init vfio_pci_core_init(void) 2138 { 2139 /* Allocate shared config space permission data used by all devices */ 2140 return vfio_pci_init_perm_bits(); 2141 } 2142 2143 module_init(vfio_pci_core_init); 2144 module_exit(vfio_pci_core_cleanup); 2145 2146 MODULE_LICENSE("GPL v2"); 2147 MODULE_AUTHOR(DRIVER_AUTHOR); 2148 MODULE_DESCRIPTION(DRIVER_DESC); 2149