1 /* 2 * drivers/pci/iov.c 3 * 4 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com> 5 * 6 * PCI Express I/O Virtualization (IOV) support. 7 * Single Root IOV 1.0 8 * Address Translation Service 1.0 9 */ 10 11 #include <linux/pci.h> 12 #include <linux/slab.h> 13 #include <linux/mutex.h> 14 #include <linux/export.h> 15 #include <linux/string.h> 16 #include <linux/delay.h> 17 #include <linux/pci-ats.h> 18 #include "pci.h" 19 20 #define VIRTFN_ID_LEN 16 21 22 static inline u8 virtfn_bus(struct pci_dev *dev, int id) 23 { 24 return dev->bus->number + ((dev->devfn + dev->sriov->offset + 25 dev->sriov->stride * id) >> 8); 26 } 27 28 static inline u8 virtfn_devfn(struct pci_dev *dev, int id) 29 { 30 return (dev->devfn + dev->sriov->offset + 31 dev->sriov->stride * id) & 0xff; 32 } 33 34 static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) 35 { 36 int rc; 37 struct pci_bus *child; 38 39 if (bus->number == busnr) 40 return bus; 41 42 child = pci_find_bus(pci_domain_nr(bus), busnr); 43 if (child) 44 return child; 45 46 child = pci_add_new_bus(bus, NULL, busnr); 47 if (!child) 48 return NULL; 49 50 child->subordinate = busnr; 51 child->dev.parent = bus->bridge; 52 rc = pci_bus_add_child(child); 53 if (rc) { 54 pci_remove_bus(child); 55 return NULL; 56 } 57 58 return child; 59 } 60 61 static void virtfn_remove_bus(struct pci_bus *bus, int busnr) 62 { 63 struct pci_bus *child; 64 65 if (bus->number == busnr) 66 return; 67 68 child = pci_find_bus(pci_domain_nr(bus), busnr); 69 BUG_ON(!child); 70 71 if (list_empty(&child->devices)) 72 pci_remove_bus(child); 73 } 74 75 static int virtfn_add(struct pci_dev *dev, int id, int reset) 76 { 77 int i; 78 int rc; 79 u64 size; 80 char buf[VIRTFN_ID_LEN]; 81 struct pci_dev *virtfn; 82 struct resource *res; 83 struct pci_sriov *iov = dev->sriov; 84 85 virtfn = alloc_pci_dev(); 86 if (!virtfn) 87 return -ENOMEM; 88 89 mutex_lock(&iov->dev->sriov->lock); 90 virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); 91 if (!virtfn->bus) { 92 kfree(virtfn); 93 mutex_unlock(&iov->dev->sriov->lock); 94 return -ENOMEM; 95 } 96 virtfn->devfn = virtfn_devfn(dev, id); 97 virtfn->vendor = dev->vendor; 98 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); 99 pci_setup_device(virtfn); 100 virtfn->dev.parent = dev->dev.parent; 101 102 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 103 res = dev->resource + PCI_IOV_RESOURCES + i; 104 if (!res->parent) 105 continue; 106 virtfn->resource[i].name = pci_name(virtfn); 107 virtfn->resource[i].flags = res->flags; 108 size = resource_size(res); 109 do_div(size, iov->total); 110 virtfn->resource[i].start = res->start + size * id; 111 virtfn->resource[i].end = virtfn->resource[i].start + size - 1; 112 rc = request_resource(res, &virtfn->resource[i]); 113 BUG_ON(rc); 114 } 115 116 if (reset) 117 __pci_reset_function(virtfn); 118 119 pci_device_add(virtfn, virtfn->bus); 120 mutex_unlock(&iov->dev->sriov->lock); 121 122 virtfn->physfn = pci_dev_get(dev); 123 virtfn->is_virtfn = 1; 124 125 rc = pci_bus_add_device(virtfn); 126 if (rc) 127 goto failed1; 128 sprintf(buf, "virtfn%u", id); 129 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); 130 if (rc) 131 goto failed1; 132 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); 133 if (rc) 134 goto failed2; 135 136 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); 137 138 return 0; 139 140 failed2: 141 sysfs_remove_link(&dev->dev.kobj, buf); 142 failed1: 143 pci_dev_put(dev); 144 mutex_lock(&iov->dev->sriov->lock); 145 pci_remove_bus_device(virtfn); 146 virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); 147 mutex_unlock(&iov->dev->sriov->lock); 148 149 return rc; 150 } 151 152 static void virtfn_remove(struct pci_dev *dev, int id, int reset) 153 { 154 char buf[VIRTFN_ID_LEN]; 155 struct pci_bus *bus; 156 struct pci_dev *virtfn; 157 struct pci_sriov *iov = dev->sriov; 158 159 bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id)); 160 if (!bus) 161 return; 162 163 virtfn = pci_get_slot(bus, virtfn_devfn(dev, id)); 164 if (!virtfn) 165 return; 166 167 pci_dev_put(virtfn); 168 169 if (reset) { 170 device_release_driver(&virtfn->dev); 171 __pci_reset_function(virtfn); 172 } 173 174 sprintf(buf, "virtfn%u", id); 175 sysfs_remove_link(&dev->dev.kobj, buf); 176 sysfs_remove_link(&virtfn->dev.kobj, "physfn"); 177 178 mutex_lock(&iov->dev->sriov->lock); 179 pci_remove_bus_device(virtfn); 180 virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); 181 mutex_unlock(&iov->dev->sriov->lock); 182 183 pci_dev_put(dev); 184 } 185 186 static int sriov_migration(struct pci_dev *dev) 187 { 188 u16 status; 189 struct pci_sriov *iov = dev->sriov; 190 191 if (!iov->nr_virtfn) 192 return 0; 193 194 if (!(iov->cap & PCI_SRIOV_CAP_VFM)) 195 return 0; 196 197 pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status); 198 if (!(status & PCI_SRIOV_STATUS_VFM)) 199 return 0; 200 201 schedule_work(&iov->mtask); 202 203 return 1; 204 } 205 206 static void sriov_migration_task(struct work_struct *work) 207 { 208 int i; 209 u8 state; 210 u16 status; 211 struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask); 212 213 for (i = iov->initial; i < iov->nr_virtfn; i++) { 214 state = readb(iov->mstate + i); 215 if (state == PCI_SRIOV_VFM_MI) { 216 writeb(PCI_SRIOV_VFM_AV, iov->mstate + i); 217 state = readb(iov->mstate + i); 218 if (state == PCI_SRIOV_VFM_AV) 219 virtfn_add(iov->self, i, 1); 220 } else if (state == PCI_SRIOV_VFM_MO) { 221 virtfn_remove(iov->self, i, 1); 222 writeb(PCI_SRIOV_VFM_UA, iov->mstate + i); 223 state = readb(iov->mstate + i); 224 if (state == PCI_SRIOV_VFM_AV) 225 virtfn_add(iov->self, i, 0); 226 } 227 } 228 229 pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status); 230 status &= ~PCI_SRIOV_STATUS_VFM; 231 pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status); 232 } 233 234 static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn) 235 { 236 int bir; 237 u32 table; 238 resource_size_t pa; 239 struct pci_sriov *iov = dev->sriov; 240 241 if (nr_virtfn <= iov->initial) 242 return 0; 243 244 pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table); 245 bir = PCI_SRIOV_VFM_BIR(table); 246 if (bir > PCI_STD_RESOURCE_END) 247 return -EIO; 248 249 table = PCI_SRIOV_VFM_OFFSET(table); 250 if (table + nr_virtfn > pci_resource_len(dev, bir)) 251 return -EIO; 252 253 pa = pci_resource_start(dev, bir) + table; 254 iov->mstate = ioremap(pa, nr_virtfn); 255 if (!iov->mstate) 256 return -ENOMEM; 257 258 INIT_WORK(&iov->mtask, sriov_migration_task); 259 260 iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR; 261 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 262 263 return 0; 264 } 265 266 static void sriov_disable_migration(struct pci_dev *dev) 267 { 268 struct pci_sriov *iov = dev->sriov; 269 270 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR); 271 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 272 273 cancel_work_sync(&iov->mtask); 274 iounmap(iov->mstate); 275 } 276 277 static int sriov_enable(struct pci_dev *dev, int nr_virtfn) 278 { 279 int rc; 280 int i, j; 281 int nres; 282 u16 offset, stride, initial; 283 struct resource *res; 284 struct pci_dev *pdev; 285 struct pci_sriov *iov = dev->sriov; 286 int bars = 0; 287 288 if (!nr_virtfn) 289 return 0; 290 291 if (iov->nr_virtfn) 292 return -EINVAL; 293 294 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); 295 if (initial > iov->total || 296 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total))) 297 return -EIO; 298 299 if (nr_virtfn < 0 || nr_virtfn > iov->total || 300 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) 301 return -EINVAL; 302 303 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); 304 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset); 305 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride); 306 if (!offset || (nr_virtfn > 1 && !stride)) 307 return -EIO; 308 309 nres = 0; 310 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 311 bars |= (1 << (i + PCI_IOV_RESOURCES)); 312 res = dev->resource + PCI_IOV_RESOURCES + i; 313 if (res->parent) 314 nres++; 315 } 316 if (nres != iov->nres) { 317 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n"); 318 return -ENOMEM; 319 } 320 321 iov->offset = offset; 322 iov->stride = stride; 323 324 if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) { 325 dev_err(&dev->dev, "SR-IOV: bus number out of range\n"); 326 return -ENOMEM; 327 } 328 329 if (pci_enable_resources(dev, bars)) { 330 dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n"); 331 return -ENOMEM; 332 } 333 334 if (iov->link != dev->devfn) { 335 pdev = pci_get_slot(dev->bus, iov->link); 336 if (!pdev) 337 return -ENODEV; 338 339 pci_dev_put(pdev); 340 341 if (!pdev->is_physfn) 342 return -ENODEV; 343 344 rc = sysfs_create_link(&dev->dev.kobj, 345 &pdev->dev.kobj, "dep_link"); 346 if (rc) 347 return rc; 348 } 349 350 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); 351 352 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; 353 pci_cfg_access_lock(dev); 354 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 355 msleep(100); 356 pci_cfg_access_unlock(dev); 357 358 iov->initial = initial; 359 if (nr_virtfn < initial) 360 initial = nr_virtfn; 361 362 for (i = 0; i < initial; i++) { 363 rc = virtfn_add(dev, i, 0); 364 if (rc) 365 goto failed; 366 } 367 368 if (iov->cap & PCI_SRIOV_CAP_VFM) { 369 rc = sriov_enable_migration(dev, nr_virtfn); 370 if (rc) 371 goto failed; 372 } 373 374 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); 375 iov->nr_virtfn = nr_virtfn; 376 377 return 0; 378 379 failed: 380 for (j = 0; j < i; j++) 381 virtfn_remove(dev, j, 0); 382 383 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 384 pci_cfg_access_lock(dev); 385 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 386 ssleep(1); 387 pci_cfg_access_unlock(dev); 388 389 if (iov->link != dev->devfn) 390 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 391 392 return rc; 393 } 394 395 static void sriov_disable(struct pci_dev *dev) 396 { 397 int i; 398 struct pci_sriov *iov = dev->sriov; 399 400 if (!iov->nr_virtfn) 401 return; 402 403 if (iov->cap & PCI_SRIOV_CAP_VFM) 404 sriov_disable_migration(dev); 405 406 for (i = 0; i < iov->nr_virtfn; i++) 407 virtfn_remove(dev, i, 0); 408 409 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 410 pci_cfg_access_lock(dev); 411 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 412 ssleep(1); 413 pci_cfg_access_unlock(dev); 414 415 if (iov->link != dev->devfn) 416 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 417 418 iov->nr_virtfn = 0; 419 } 420 421 static int sriov_init(struct pci_dev *dev, int pos) 422 { 423 int i; 424 int rc; 425 int nres; 426 u32 pgsz; 427 u16 ctrl, total, offset, stride; 428 struct pci_sriov *iov; 429 struct resource *res; 430 struct pci_dev *pdev; 431 432 if (dev->pcie_type != PCI_EXP_TYPE_RC_END && 433 dev->pcie_type != PCI_EXP_TYPE_ENDPOINT) 434 return -ENODEV; 435 436 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); 437 if (ctrl & PCI_SRIOV_CTRL_VFE) { 438 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); 439 ssleep(1); 440 } 441 442 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); 443 if (!total) 444 return 0; 445 446 ctrl = 0; 447 list_for_each_entry(pdev, &dev->bus->devices, bus_list) 448 if (pdev->is_physfn) 449 goto found; 450 451 pdev = NULL; 452 if (pci_ari_enabled(dev->bus)) 453 ctrl |= PCI_SRIOV_CTRL_ARI; 454 455 found: 456 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); 457 pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset); 458 pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride); 459 if (!offset || (total > 1 && !stride)) 460 return -EIO; 461 462 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); 463 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; 464 pgsz &= ~((1 << i) - 1); 465 if (!pgsz) 466 return -EIO; 467 468 pgsz &= ~(pgsz - 1); 469 470 nres = 0; 471 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 472 res = dev->resource + PCI_IOV_RESOURCES + i; 473 i += __pci_read_base(dev, pci_bar_unknown, res, 474 pos + PCI_SRIOV_BAR + i * 4); 475 if (!res->flags) 476 continue; 477 if (resource_size(res) & (PAGE_SIZE - 1)) { 478 rc = -EIO; 479 goto failed; 480 } 481 res->end = res->start + resource_size(res) * total - 1; 482 nres++; 483 } 484 485 iov = kzalloc(sizeof(*iov), GFP_KERNEL); 486 if (!iov) { 487 rc = -ENOMEM; 488 goto failed; 489 } 490 491 iov->pos = pos; 492 iov->nres = nres; 493 iov->ctrl = ctrl; 494 iov->total = total; 495 iov->offset = offset; 496 iov->stride = stride; 497 iov->pgsz = pgsz; 498 iov->self = dev; 499 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); 500 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); 501 if (dev->pcie_type == PCI_EXP_TYPE_RC_END) 502 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link); 503 504 if (pdev) 505 iov->dev = pci_dev_get(pdev); 506 else 507 iov->dev = dev; 508 509 mutex_init(&iov->lock); 510 511 dev->sriov = iov; 512 dev->is_physfn = 1; 513 514 return 0; 515 516 failed: 517 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 518 res = dev->resource + PCI_IOV_RESOURCES + i; 519 res->flags = 0; 520 } 521 522 return rc; 523 } 524 525 static void sriov_release(struct pci_dev *dev) 526 { 527 BUG_ON(dev->sriov->nr_virtfn); 528 529 if (dev != dev->sriov->dev) 530 pci_dev_put(dev->sriov->dev); 531 532 mutex_destroy(&dev->sriov->lock); 533 534 kfree(dev->sriov); 535 dev->sriov = NULL; 536 } 537 538 static void sriov_restore_state(struct pci_dev *dev) 539 { 540 int i; 541 u16 ctrl; 542 struct pci_sriov *iov = dev->sriov; 543 544 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); 545 if (ctrl & PCI_SRIOV_CTRL_VFE) 546 return; 547 548 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) 549 pci_update_resource(dev, i); 550 551 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); 552 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn); 553 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 554 if (iov->ctrl & PCI_SRIOV_CTRL_VFE) 555 msleep(100); 556 } 557 558 /** 559 * pci_iov_init - initialize the IOV capability 560 * @dev: the PCI device 561 * 562 * Returns 0 on success, or negative on failure. 563 */ 564 int pci_iov_init(struct pci_dev *dev) 565 { 566 int pos; 567 568 if (!pci_is_pcie(dev)) 569 return -ENODEV; 570 571 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); 572 if (pos) 573 return sriov_init(dev, pos); 574 575 return -ENODEV; 576 } 577 578 /** 579 * pci_iov_release - release resources used by the IOV capability 580 * @dev: the PCI device 581 */ 582 void pci_iov_release(struct pci_dev *dev) 583 { 584 if (dev->is_physfn) 585 sriov_release(dev); 586 } 587 588 /** 589 * pci_iov_resource_bar - get position of the SR-IOV BAR 590 * @dev: the PCI device 591 * @resno: the resource number 592 * @type: the BAR type to be filled in 593 * 594 * Returns position of the BAR encapsulated in the SR-IOV capability. 595 */ 596 int pci_iov_resource_bar(struct pci_dev *dev, int resno, 597 enum pci_bar_type *type) 598 { 599 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END) 600 return 0; 601 602 BUG_ON(!dev->is_physfn); 603 604 *type = pci_bar_unknown; 605 606 return dev->sriov->pos + PCI_SRIOV_BAR + 607 4 * (resno - PCI_IOV_RESOURCES); 608 } 609 610 /** 611 * pci_sriov_resource_alignment - get resource alignment for VF BAR 612 * @dev: the PCI device 613 * @resno: the resource number 614 * 615 * Returns the alignment of the VF BAR found in the SR-IOV capability. 616 * This is not the same as the resource size which is defined as 617 * the VF BAR size multiplied by the number of VFs. The alignment 618 * is just the VF BAR size. 619 */ 620 resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno) 621 { 622 struct resource tmp; 623 enum pci_bar_type type; 624 int reg = pci_iov_resource_bar(dev, resno, &type); 625 626 if (!reg) 627 return 0; 628 629 __pci_read_base(dev, type, &tmp, reg); 630 return resource_alignment(&tmp); 631 } 632 633 /** 634 * pci_restore_iov_state - restore the state of the IOV capability 635 * @dev: the PCI device 636 */ 637 void pci_restore_iov_state(struct pci_dev *dev) 638 { 639 if (dev->is_physfn) 640 sriov_restore_state(dev); 641 } 642 643 /** 644 * pci_iov_bus_range - find bus range used by Virtual Function 645 * @bus: the PCI bus 646 * 647 * Returns max number of buses (exclude current one) used by Virtual 648 * Functions. 649 */ 650 int pci_iov_bus_range(struct pci_bus *bus) 651 { 652 int max = 0; 653 u8 busnr; 654 struct pci_dev *dev; 655 656 list_for_each_entry(dev, &bus->devices, bus_list) { 657 if (!dev->is_physfn) 658 continue; 659 busnr = virtfn_bus(dev, dev->sriov->total - 1); 660 if (busnr > max) 661 max = busnr; 662 } 663 664 return max ? max - bus->number : 0; 665 } 666 667 /** 668 * pci_enable_sriov - enable the SR-IOV capability 669 * @dev: the PCI device 670 * @nr_virtfn: number of virtual functions to enable 671 * 672 * Returns 0 on success, or negative on failure. 673 */ 674 int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) 675 { 676 might_sleep(); 677 678 if (!dev->is_physfn) 679 return -ENODEV; 680 681 return sriov_enable(dev, nr_virtfn); 682 } 683 EXPORT_SYMBOL_GPL(pci_enable_sriov); 684 685 /** 686 * pci_disable_sriov - disable the SR-IOV capability 687 * @dev: the PCI device 688 */ 689 void pci_disable_sriov(struct pci_dev *dev) 690 { 691 might_sleep(); 692 693 if (!dev->is_physfn) 694 return; 695 696 sriov_disable(dev); 697 } 698 EXPORT_SYMBOL_GPL(pci_disable_sriov); 699 700 /** 701 * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration 702 * @dev: the PCI device 703 * 704 * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not. 705 * 706 * Physical Function driver is responsible to register IRQ handler using 707 * VF Migration Interrupt Message Number, and call this function when the 708 * interrupt is generated by the hardware. 709 */ 710 irqreturn_t pci_sriov_migration(struct pci_dev *dev) 711 { 712 if (!dev->is_physfn) 713 return IRQ_NONE; 714 715 return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE; 716 } 717 EXPORT_SYMBOL_GPL(pci_sriov_migration); 718 719 /** 720 * pci_num_vf - return number of VFs associated with a PF device_release_driver 721 * @dev: the PCI device 722 * 723 * Returns number of VFs, or 0 if SR-IOV is not enabled. 724 */ 725 int pci_num_vf(struct pci_dev *dev) 726 { 727 if (!dev || !dev->is_physfn) 728 return 0; 729 else 730 return dev->sriov->nr_virtfn; 731 } 732 EXPORT_SYMBOL_GPL(pci_num_vf); 733