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 struct pci_bus *child; 37 38 if (bus->number == busnr) 39 return bus; 40 41 child = pci_find_bus(pci_domain_nr(bus), busnr); 42 if (child) 43 return child; 44 45 child = pci_add_new_bus(bus, NULL, busnr); 46 if (!child) 47 return NULL; 48 49 pci_bus_insert_busn_res(child, busnr, busnr); 50 51 return child; 52 } 53 54 static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) 55 { 56 if (physbus != virtbus && list_empty(&virtbus->devices)) 57 pci_remove_bus(virtbus); 58 } 59 60 static int virtfn_add(struct pci_dev *dev, int id, int reset) 61 { 62 int i; 63 int rc = -ENOMEM; 64 u64 size; 65 char buf[VIRTFN_ID_LEN]; 66 struct pci_dev *virtfn; 67 struct resource *res; 68 struct pci_sriov *iov = dev->sriov; 69 struct pci_bus *bus; 70 71 mutex_lock(&iov->dev->sriov->lock); 72 bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); 73 if (!bus) 74 goto failed; 75 76 virtfn = pci_alloc_dev(bus); 77 if (!virtfn) 78 goto failed0; 79 80 virtfn->devfn = virtfn_devfn(dev, id); 81 virtfn->vendor = dev->vendor; 82 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); 83 pci_setup_device(virtfn); 84 virtfn->dev.parent = dev->dev.parent; 85 virtfn->physfn = pci_dev_get(dev); 86 virtfn->is_virtfn = 1; 87 virtfn->multifunction = 0; 88 89 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 90 res = dev->resource + PCI_IOV_RESOURCES + i; 91 if (!res->parent) 92 continue; 93 virtfn->resource[i].name = pci_name(virtfn); 94 virtfn->resource[i].flags = res->flags; 95 size = resource_size(res); 96 do_div(size, iov->total_VFs); 97 virtfn->resource[i].start = res->start + size * id; 98 virtfn->resource[i].end = virtfn->resource[i].start + size - 1; 99 rc = request_resource(res, &virtfn->resource[i]); 100 BUG_ON(rc); 101 } 102 103 if (reset) 104 __pci_reset_function(virtfn); 105 106 pci_device_add(virtfn, virtfn->bus); 107 mutex_unlock(&iov->dev->sriov->lock); 108 109 rc = pci_bus_add_device(virtfn); 110 sprintf(buf, "virtfn%u", id); 111 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); 112 if (rc) 113 goto failed1; 114 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); 115 if (rc) 116 goto failed2; 117 118 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); 119 120 return 0; 121 122 failed2: 123 sysfs_remove_link(&dev->dev.kobj, buf); 124 failed1: 125 pci_dev_put(dev); 126 mutex_lock(&iov->dev->sriov->lock); 127 pci_stop_and_remove_bus_device(virtfn); 128 failed0: 129 virtfn_remove_bus(dev->bus, bus); 130 failed: 131 mutex_unlock(&iov->dev->sriov->lock); 132 133 return rc; 134 } 135 136 static void virtfn_remove(struct pci_dev *dev, int id, int reset) 137 { 138 char buf[VIRTFN_ID_LEN]; 139 struct pci_dev *virtfn; 140 struct pci_sriov *iov = dev->sriov; 141 142 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), 143 virtfn_bus(dev, id), 144 virtfn_devfn(dev, id)); 145 if (!virtfn) 146 return; 147 148 if (reset) { 149 device_release_driver(&virtfn->dev); 150 __pci_reset_function(virtfn); 151 } 152 153 sprintf(buf, "virtfn%u", id); 154 sysfs_remove_link(&dev->dev.kobj, buf); 155 /* 156 * pci_stop_dev() could have been called for this virtfn already, 157 * so the directory for the virtfn may have been removed before. 158 * Double check to avoid spurious sysfs warnings. 159 */ 160 if (virtfn->dev.kobj.sd) 161 sysfs_remove_link(&virtfn->dev.kobj, "physfn"); 162 163 mutex_lock(&iov->dev->sriov->lock); 164 pci_stop_and_remove_bus_device(virtfn); 165 virtfn_remove_bus(dev->bus, virtfn->bus); 166 mutex_unlock(&iov->dev->sriov->lock); 167 168 /* balance pci_get_domain_bus_and_slot() */ 169 pci_dev_put(virtfn); 170 pci_dev_put(dev); 171 } 172 173 static int sriov_migration(struct pci_dev *dev) 174 { 175 u16 status; 176 struct pci_sriov *iov = dev->sriov; 177 178 if (!iov->num_VFs) 179 return 0; 180 181 if (!(iov->cap & PCI_SRIOV_CAP_VFM)) 182 return 0; 183 184 pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status); 185 if (!(status & PCI_SRIOV_STATUS_VFM)) 186 return 0; 187 188 schedule_work(&iov->mtask); 189 190 return 1; 191 } 192 193 static void sriov_migration_task(struct work_struct *work) 194 { 195 int i; 196 u8 state; 197 u16 status; 198 struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask); 199 200 for (i = iov->initial_VFs; i < iov->num_VFs; i++) { 201 state = readb(iov->mstate + i); 202 if (state == PCI_SRIOV_VFM_MI) { 203 writeb(PCI_SRIOV_VFM_AV, iov->mstate + i); 204 state = readb(iov->mstate + i); 205 if (state == PCI_SRIOV_VFM_AV) 206 virtfn_add(iov->self, i, 1); 207 } else if (state == PCI_SRIOV_VFM_MO) { 208 virtfn_remove(iov->self, i, 1); 209 writeb(PCI_SRIOV_VFM_UA, iov->mstate + i); 210 state = readb(iov->mstate + i); 211 if (state == PCI_SRIOV_VFM_AV) 212 virtfn_add(iov->self, i, 0); 213 } 214 } 215 216 pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status); 217 status &= ~PCI_SRIOV_STATUS_VFM; 218 pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status); 219 } 220 221 static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn) 222 { 223 int bir; 224 u32 table; 225 resource_size_t pa; 226 struct pci_sriov *iov = dev->sriov; 227 228 if (nr_virtfn <= iov->initial_VFs) 229 return 0; 230 231 pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table); 232 bir = PCI_SRIOV_VFM_BIR(table); 233 if (bir > PCI_STD_RESOURCE_END) 234 return -EIO; 235 236 table = PCI_SRIOV_VFM_OFFSET(table); 237 if (table + nr_virtfn > pci_resource_len(dev, bir)) 238 return -EIO; 239 240 pa = pci_resource_start(dev, bir) + table; 241 iov->mstate = ioremap(pa, nr_virtfn); 242 if (!iov->mstate) 243 return -ENOMEM; 244 245 INIT_WORK(&iov->mtask, sriov_migration_task); 246 247 iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR; 248 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 249 250 return 0; 251 } 252 253 static void sriov_disable_migration(struct pci_dev *dev) 254 { 255 struct pci_sriov *iov = dev->sriov; 256 257 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR); 258 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 259 260 cancel_work_sync(&iov->mtask); 261 iounmap(iov->mstate); 262 } 263 264 static int sriov_enable(struct pci_dev *dev, int nr_virtfn) 265 { 266 int rc; 267 int i, j; 268 int nres; 269 u16 offset, stride, initial; 270 struct resource *res; 271 struct pci_dev *pdev; 272 struct pci_sriov *iov = dev->sriov; 273 int bars = 0; 274 275 if (!nr_virtfn) 276 return 0; 277 278 if (iov->num_VFs) 279 return -EINVAL; 280 281 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); 282 if (initial > iov->total_VFs || 283 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs))) 284 return -EIO; 285 286 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs || 287 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) 288 return -EINVAL; 289 290 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset); 291 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride); 292 if (!offset || (nr_virtfn > 1 && !stride)) 293 return -EIO; 294 295 nres = 0; 296 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 297 bars |= (1 << (i + PCI_IOV_RESOURCES)); 298 res = dev->resource + PCI_IOV_RESOURCES + i; 299 if (res->parent) 300 nres++; 301 } 302 if (nres != iov->nres) { 303 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n"); 304 return -ENOMEM; 305 } 306 307 iov->offset = offset; 308 iov->stride = stride; 309 310 if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->busn_res.end) { 311 dev_err(&dev->dev, "SR-IOV: bus number out of range\n"); 312 return -ENOMEM; 313 } 314 315 if (pci_enable_resources(dev, bars)) { 316 dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n"); 317 return -ENOMEM; 318 } 319 320 if (iov->link != dev->devfn) { 321 pdev = pci_get_slot(dev->bus, iov->link); 322 if (!pdev) 323 return -ENODEV; 324 325 if (!pdev->is_physfn) { 326 pci_dev_put(pdev); 327 return -ENOSYS; 328 } 329 330 rc = sysfs_create_link(&dev->dev.kobj, 331 &pdev->dev.kobj, "dep_link"); 332 pci_dev_put(pdev); 333 if (rc) 334 return rc; 335 } 336 337 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); 338 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; 339 pci_cfg_access_lock(dev); 340 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 341 msleep(100); 342 pci_cfg_access_unlock(dev); 343 344 iov->initial_VFs = initial; 345 if (nr_virtfn < initial) 346 initial = nr_virtfn; 347 348 for (i = 0; i < initial; i++) { 349 rc = virtfn_add(dev, i, 0); 350 if (rc) 351 goto failed; 352 } 353 354 if (iov->cap & PCI_SRIOV_CAP_VFM) { 355 rc = sriov_enable_migration(dev, nr_virtfn); 356 if (rc) 357 goto failed; 358 } 359 360 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); 361 iov->num_VFs = nr_virtfn; 362 363 return 0; 364 365 failed: 366 for (j = 0; j < i; j++) 367 virtfn_remove(dev, j, 0); 368 369 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 370 pci_cfg_access_lock(dev); 371 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 372 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0); 373 ssleep(1); 374 pci_cfg_access_unlock(dev); 375 376 if (iov->link != dev->devfn) 377 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 378 379 return rc; 380 } 381 382 static void sriov_disable(struct pci_dev *dev) 383 { 384 int i; 385 struct pci_sriov *iov = dev->sriov; 386 387 if (!iov->num_VFs) 388 return; 389 390 if (iov->cap & PCI_SRIOV_CAP_VFM) 391 sriov_disable_migration(dev); 392 393 for (i = 0; i < iov->num_VFs; i++) 394 virtfn_remove(dev, i, 0); 395 396 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 397 pci_cfg_access_lock(dev); 398 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 399 ssleep(1); 400 pci_cfg_access_unlock(dev); 401 402 if (iov->link != dev->devfn) 403 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 404 405 iov->num_VFs = 0; 406 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0); 407 } 408 409 static int sriov_init(struct pci_dev *dev, int pos) 410 { 411 int i; 412 int rc; 413 int nres; 414 u32 pgsz; 415 u16 ctrl, total, offset, stride; 416 struct pci_sriov *iov; 417 struct resource *res; 418 struct pci_dev *pdev; 419 420 if (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_END && 421 pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) 422 return -ENODEV; 423 424 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); 425 if (ctrl & PCI_SRIOV_CTRL_VFE) { 426 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); 427 ssleep(1); 428 } 429 430 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); 431 if (!total) 432 return 0; 433 434 ctrl = 0; 435 list_for_each_entry(pdev, &dev->bus->devices, bus_list) 436 if (pdev->is_physfn) 437 goto found; 438 439 pdev = NULL; 440 if (pci_ari_enabled(dev->bus)) 441 ctrl |= PCI_SRIOV_CTRL_ARI; 442 443 found: 444 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); 445 pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, 0); 446 pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset); 447 pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride); 448 if (!offset || (total > 1 && !stride)) 449 return -EIO; 450 451 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); 452 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; 453 pgsz &= ~((1 << i) - 1); 454 if (!pgsz) 455 return -EIO; 456 457 pgsz &= ~(pgsz - 1); 458 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz); 459 460 nres = 0; 461 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 462 res = dev->resource + PCI_IOV_RESOURCES + i; 463 i += __pci_read_base(dev, pci_bar_unknown, res, 464 pos + PCI_SRIOV_BAR + i * 4); 465 if (!res->flags) 466 continue; 467 if (resource_size(res) & (PAGE_SIZE - 1)) { 468 rc = -EIO; 469 goto failed; 470 } 471 res->end = res->start + resource_size(res) * total - 1; 472 nres++; 473 } 474 475 iov = kzalloc(sizeof(*iov), GFP_KERNEL); 476 if (!iov) { 477 rc = -ENOMEM; 478 goto failed; 479 } 480 481 iov->pos = pos; 482 iov->nres = nres; 483 iov->ctrl = ctrl; 484 iov->total_VFs = total; 485 iov->offset = offset; 486 iov->stride = stride; 487 iov->pgsz = pgsz; 488 iov->self = dev; 489 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); 490 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); 491 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) 492 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link); 493 494 if (pdev) 495 iov->dev = pci_dev_get(pdev); 496 else 497 iov->dev = dev; 498 499 mutex_init(&iov->lock); 500 501 dev->sriov = iov; 502 dev->is_physfn = 1; 503 504 return 0; 505 506 failed: 507 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 508 res = dev->resource + PCI_IOV_RESOURCES + i; 509 res->flags = 0; 510 } 511 512 return rc; 513 } 514 515 static void sriov_release(struct pci_dev *dev) 516 { 517 BUG_ON(dev->sriov->num_VFs); 518 519 if (dev != dev->sriov->dev) 520 pci_dev_put(dev->sriov->dev); 521 522 mutex_destroy(&dev->sriov->lock); 523 524 kfree(dev->sriov); 525 dev->sriov = NULL; 526 } 527 528 static void sriov_restore_state(struct pci_dev *dev) 529 { 530 int i; 531 u16 ctrl; 532 struct pci_sriov *iov = dev->sriov; 533 534 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); 535 if (ctrl & PCI_SRIOV_CTRL_VFE) 536 return; 537 538 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) 539 pci_update_resource(dev, i); 540 541 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); 542 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->num_VFs); 543 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 544 if (iov->ctrl & PCI_SRIOV_CTRL_VFE) 545 msleep(100); 546 } 547 548 /** 549 * pci_iov_init - initialize the IOV capability 550 * @dev: the PCI device 551 * 552 * Returns 0 on success, or negative on failure. 553 */ 554 int pci_iov_init(struct pci_dev *dev) 555 { 556 int pos; 557 558 if (!pci_is_pcie(dev)) 559 return -ENODEV; 560 561 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); 562 if (pos) 563 return sriov_init(dev, pos); 564 565 return -ENODEV; 566 } 567 568 /** 569 * pci_iov_release - release resources used by the IOV capability 570 * @dev: the PCI device 571 */ 572 void pci_iov_release(struct pci_dev *dev) 573 { 574 if (dev->is_physfn) 575 sriov_release(dev); 576 } 577 578 /** 579 * pci_iov_resource_bar - get position of the SR-IOV BAR 580 * @dev: the PCI device 581 * @resno: the resource number 582 * @type: the BAR type to be filled in 583 * 584 * Returns position of the BAR encapsulated in the SR-IOV capability. 585 */ 586 int pci_iov_resource_bar(struct pci_dev *dev, int resno, 587 enum pci_bar_type *type) 588 { 589 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END) 590 return 0; 591 592 BUG_ON(!dev->is_physfn); 593 594 *type = pci_bar_unknown; 595 596 return dev->sriov->pos + PCI_SRIOV_BAR + 597 4 * (resno - PCI_IOV_RESOURCES); 598 } 599 600 /** 601 * pci_sriov_resource_alignment - get resource alignment for VF BAR 602 * @dev: the PCI device 603 * @resno: the resource number 604 * 605 * Returns the alignment of the VF BAR found in the SR-IOV capability. 606 * This is not the same as the resource size which is defined as 607 * the VF BAR size multiplied by the number of VFs. The alignment 608 * is just the VF BAR size. 609 */ 610 resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno) 611 { 612 struct resource tmp; 613 enum pci_bar_type type; 614 int reg = pci_iov_resource_bar(dev, resno, &type); 615 616 if (!reg) 617 return 0; 618 619 __pci_read_base(dev, type, &tmp, reg); 620 return resource_alignment(&tmp); 621 } 622 623 /** 624 * pci_restore_iov_state - restore the state of the IOV capability 625 * @dev: the PCI device 626 */ 627 void pci_restore_iov_state(struct pci_dev *dev) 628 { 629 if (dev->is_physfn) 630 sriov_restore_state(dev); 631 } 632 633 /** 634 * pci_iov_bus_range - find bus range used by Virtual Function 635 * @bus: the PCI bus 636 * 637 * Returns max number of buses (exclude current one) used by Virtual 638 * Functions. 639 */ 640 int pci_iov_bus_range(struct pci_bus *bus) 641 { 642 int max = 0; 643 u8 busnr; 644 struct pci_dev *dev; 645 646 list_for_each_entry(dev, &bus->devices, bus_list) { 647 if (!dev->is_physfn) 648 continue; 649 busnr = virtfn_bus(dev, dev->sriov->total_VFs - 1); 650 if (busnr > max) 651 max = busnr; 652 } 653 654 return max ? max - bus->number : 0; 655 } 656 657 /** 658 * pci_enable_sriov - enable the SR-IOV capability 659 * @dev: the PCI device 660 * @nr_virtfn: number of virtual functions to enable 661 * 662 * Returns 0 on success, or negative on failure. 663 */ 664 int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) 665 { 666 might_sleep(); 667 668 if (!dev->is_physfn) 669 return -ENOSYS; 670 671 return sriov_enable(dev, nr_virtfn); 672 } 673 EXPORT_SYMBOL_GPL(pci_enable_sriov); 674 675 /** 676 * pci_disable_sriov - disable the SR-IOV capability 677 * @dev: the PCI device 678 */ 679 void pci_disable_sriov(struct pci_dev *dev) 680 { 681 might_sleep(); 682 683 if (!dev->is_physfn) 684 return; 685 686 sriov_disable(dev); 687 } 688 EXPORT_SYMBOL_GPL(pci_disable_sriov); 689 690 /** 691 * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration 692 * @dev: the PCI device 693 * 694 * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not. 695 * 696 * Physical Function driver is responsible to register IRQ handler using 697 * VF Migration Interrupt Message Number, and call this function when the 698 * interrupt is generated by the hardware. 699 */ 700 irqreturn_t pci_sriov_migration(struct pci_dev *dev) 701 { 702 if (!dev->is_physfn) 703 return IRQ_NONE; 704 705 return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE; 706 } 707 EXPORT_SYMBOL_GPL(pci_sriov_migration); 708 709 /** 710 * pci_num_vf - return number of VFs associated with a PF device_release_driver 711 * @dev: the PCI device 712 * 713 * Returns number of VFs, or 0 if SR-IOV is not enabled. 714 */ 715 int pci_num_vf(struct pci_dev *dev) 716 { 717 if (!dev->is_physfn) 718 return 0; 719 720 return dev->sriov->num_VFs; 721 } 722 EXPORT_SYMBOL_GPL(pci_num_vf); 723 724 /** 725 * pci_vfs_assigned - returns number of VFs are assigned to a guest 726 * @dev: the PCI device 727 * 728 * Returns number of VFs belonging to this device that are assigned to a guest. 729 * If device is not a physical function returns 0. 730 */ 731 int pci_vfs_assigned(struct pci_dev *dev) 732 { 733 struct pci_dev *vfdev; 734 unsigned int vfs_assigned = 0; 735 unsigned short dev_id; 736 737 /* only search if we are a PF */ 738 if (!dev->is_physfn) 739 return 0; 740 741 /* 742 * determine the device ID for the VFs, the vendor ID will be the 743 * same as the PF so there is no need to check for that one 744 */ 745 pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_VF_DID, &dev_id); 746 747 /* loop through all the VFs to see if we own any that are assigned */ 748 vfdev = pci_get_device(dev->vendor, dev_id, NULL); 749 while (vfdev) { 750 /* 751 * It is considered assigned if it is a virtual function with 752 * our dev as the physical function and the assigned bit is set 753 */ 754 if (vfdev->is_virtfn && (vfdev->physfn == dev) && 755 (vfdev->dev_flags & PCI_DEV_FLAGS_ASSIGNED)) 756 vfs_assigned++; 757 758 vfdev = pci_get_device(dev->vendor, dev_id, vfdev); 759 } 760 761 return vfs_assigned; 762 } 763 EXPORT_SYMBOL_GPL(pci_vfs_assigned); 764 765 /** 766 * pci_sriov_set_totalvfs -- reduce the TotalVFs available 767 * @dev: the PCI PF device 768 * @numvfs: number that should be used for TotalVFs supported 769 * 770 * Should be called from PF driver's probe routine with 771 * device's mutex held. 772 * 773 * Returns 0 if PF is an SRIOV-capable device and 774 * value of numvfs valid. If not a PF return -ENOSYS; 775 * if numvfs is invalid return -EINVAL; 776 * if VFs already enabled, return -EBUSY. 777 */ 778 int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs) 779 { 780 if (!dev->is_physfn) 781 return -ENOSYS; 782 if (numvfs > dev->sriov->total_VFs) 783 return -EINVAL; 784 785 /* Shouldn't change if VFs already enabled */ 786 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE) 787 return -EBUSY; 788 else 789 dev->sriov->driver_max_VFs = numvfs; 790 791 return 0; 792 } 793 EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs); 794 795 /** 796 * pci_sriov_get_totalvfs -- get total VFs supported on this device 797 * @dev: the PCI PF device 798 * 799 * For a PCIe device with SRIOV support, return the PCIe 800 * SRIOV capability value of TotalVFs or the value of driver_max_VFs 801 * if the driver reduced it. Otherwise 0. 802 */ 803 int pci_sriov_get_totalvfs(struct pci_dev *dev) 804 { 805 if (!dev->is_physfn) 806 return 0; 807 808 if (dev->sriov->driver_max_VFs) 809 return dev->sriov->driver_max_VFs; 810 811 return dev->sriov->total_VFs; 812 } 813 EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs); 814