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 int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id) 23 { 24 if (!dev->is_physfn) 25 return -EINVAL; 26 return dev->bus->number + ((dev->devfn + dev->sriov->offset + 27 dev->sriov->stride * vf_id) >> 8); 28 } 29 30 int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id) 31 { 32 if (!dev->is_physfn) 33 return -EINVAL; 34 return (dev->devfn + dev->sriov->offset + 35 dev->sriov->stride * vf_id) & 0xff; 36 } 37 38 /* 39 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may 40 * change when NumVFs changes. 41 * 42 * Update iov->offset and iov->stride when NumVFs is written. 43 */ 44 static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn) 45 { 46 struct pci_sriov *iov = dev->sriov; 47 48 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); 49 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset); 50 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride); 51 } 52 53 /* 54 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride 55 * determine how many additional bus numbers will be consumed by VFs. 56 * 57 * Iterate over all valid NumVFs and calculate the maximum number of bus 58 * numbers that could ever be required. 59 */ 60 static inline u8 virtfn_max_buses(struct pci_dev *dev) 61 { 62 struct pci_sriov *iov = dev->sriov; 63 int nr_virtfn; 64 u8 max = 0; 65 int busnr; 66 67 for (nr_virtfn = 1; nr_virtfn <= iov->total_VFs; nr_virtfn++) { 68 pci_iov_set_numvfs(dev, nr_virtfn); 69 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1); 70 if (busnr > max) 71 max = busnr; 72 } 73 74 return max; 75 } 76 77 static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) 78 { 79 struct pci_bus *child; 80 81 if (bus->number == busnr) 82 return bus; 83 84 child = pci_find_bus(pci_domain_nr(bus), busnr); 85 if (child) 86 return child; 87 88 child = pci_add_new_bus(bus, NULL, busnr); 89 if (!child) 90 return NULL; 91 92 pci_bus_insert_busn_res(child, busnr, busnr); 93 94 return child; 95 } 96 97 static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) 98 { 99 if (physbus != virtbus && list_empty(&virtbus->devices)) 100 pci_remove_bus(virtbus); 101 } 102 103 resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno) 104 { 105 if (!dev->is_physfn) 106 return 0; 107 108 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES]; 109 } 110 111 static int virtfn_add(struct pci_dev *dev, int id, int reset) 112 { 113 int i; 114 int rc = -ENOMEM; 115 u64 size; 116 char buf[VIRTFN_ID_LEN]; 117 struct pci_dev *virtfn; 118 struct resource *res; 119 struct pci_sriov *iov = dev->sriov; 120 struct pci_bus *bus; 121 122 mutex_lock(&iov->dev->sriov->lock); 123 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id)); 124 if (!bus) 125 goto failed; 126 127 virtfn = pci_alloc_dev(bus); 128 if (!virtfn) 129 goto failed0; 130 131 virtfn->devfn = pci_iov_virtfn_devfn(dev, id); 132 virtfn->vendor = dev->vendor; 133 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); 134 pci_setup_device(virtfn); 135 virtfn->dev.parent = dev->dev.parent; 136 virtfn->physfn = pci_dev_get(dev); 137 virtfn->is_virtfn = 1; 138 virtfn->multifunction = 0; 139 140 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 141 res = &dev->resource[i + PCI_IOV_RESOURCES]; 142 if (!res->parent) 143 continue; 144 virtfn->resource[i].name = pci_name(virtfn); 145 virtfn->resource[i].flags = res->flags; 146 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES); 147 virtfn->resource[i].start = res->start + size * id; 148 virtfn->resource[i].end = virtfn->resource[i].start + size - 1; 149 rc = request_resource(res, &virtfn->resource[i]); 150 BUG_ON(rc); 151 } 152 153 if (reset) 154 __pci_reset_function(virtfn); 155 156 pci_device_add(virtfn, virtfn->bus); 157 mutex_unlock(&iov->dev->sriov->lock); 158 159 pci_bus_add_device(virtfn); 160 sprintf(buf, "virtfn%u", id); 161 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); 162 if (rc) 163 goto failed1; 164 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); 165 if (rc) 166 goto failed2; 167 168 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); 169 170 return 0; 171 172 failed2: 173 sysfs_remove_link(&dev->dev.kobj, buf); 174 failed1: 175 pci_dev_put(dev); 176 mutex_lock(&iov->dev->sriov->lock); 177 pci_stop_and_remove_bus_device(virtfn); 178 failed0: 179 virtfn_remove_bus(dev->bus, bus); 180 failed: 181 mutex_unlock(&iov->dev->sriov->lock); 182 183 return rc; 184 } 185 186 static void virtfn_remove(struct pci_dev *dev, int id, int reset) 187 { 188 char buf[VIRTFN_ID_LEN]; 189 struct pci_dev *virtfn; 190 struct pci_sriov *iov = dev->sriov; 191 192 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), 193 pci_iov_virtfn_bus(dev, id), 194 pci_iov_virtfn_devfn(dev, id)); 195 if (!virtfn) 196 return; 197 198 if (reset) { 199 device_release_driver(&virtfn->dev); 200 __pci_reset_function(virtfn); 201 } 202 203 sprintf(buf, "virtfn%u", id); 204 sysfs_remove_link(&dev->dev.kobj, buf); 205 /* 206 * pci_stop_dev() could have been called for this virtfn already, 207 * so the directory for the virtfn may have been removed before. 208 * Double check to avoid spurious sysfs warnings. 209 */ 210 if (virtfn->dev.kobj.sd) 211 sysfs_remove_link(&virtfn->dev.kobj, "physfn"); 212 213 mutex_lock(&iov->dev->sriov->lock); 214 pci_stop_and_remove_bus_device(virtfn); 215 virtfn_remove_bus(dev->bus, virtfn->bus); 216 mutex_unlock(&iov->dev->sriov->lock); 217 218 /* balance pci_get_domain_bus_and_slot() */ 219 pci_dev_put(virtfn); 220 pci_dev_put(dev); 221 } 222 223 int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs) 224 { 225 return 0; 226 } 227 228 static int sriov_enable(struct pci_dev *dev, int nr_virtfn) 229 { 230 int rc; 231 int i, j; 232 int nres; 233 u16 offset, stride, initial; 234 struct resource *res; 235 struct pci_dev *pdev; 236 struct pci_sriov *iov = dev->sriov; 237 int bars = 0; 238 int bus; 239 int retval; 240 241 if (!nr_virtfn) 242 return 0; 243 244 if (iov->num_VFs) 245 return -EINVAL; 246 247 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); 248 if (initial > iov->total_VFs || 249 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs))) 250 return -EIO; 251 252 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs || 253 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) 254 return -EINVAL; 255 256 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset); 257 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride); 258 if (!offset || (nr_virtfn > 1 && !stride)) 259 return -EIO; 260 261 nres = 0; 262 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 263 bars |= (1 << (i + PCI_IOV_RESOURCES)); 264 res = &dev->resource[i + PCI_IOV_RESOURCES]; 265 if (res->parent) 266 nres++; 267 } 268 if (nres != iov->nres) { 269 dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n"); 270 return -ENOMEM; 271 } 272 273 iov->offset = offset; 274 iov->stride = stride; 275 276 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1); 277 if (bus > dev->bus->busn_res.end) { 278 dev_err(&dev->dev, "can't enable %d VFs (bus %02x out of range of %pR)\n", 279 nr_virtfn, bus, &dev->bus->busn_res); 280 return -ENOMEM; 281 } 282 283 if (pci_enable_resources(dev, bars)) { 284 dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n"); 285 return -ENOMEM; 286 } 287 288 if (iov->link != dev->devfn) { 289 pdev = pci_get_slot(dev->bus, iov->link); 290 if (!pdev) 291 return -ENODEV; 292 293 if (!pdev->is_physfn) { 294 pci_dev_put(pdev); 295 return -ENOSYS; 296 } 297 298 rc = sysfs_create_link(&dev->dev.kobj, 299 &pdev->dev.kobj, "dep_link"); 300 pci_dev_put(pdev); 301 if (rc) 302 return rc; 303 } 304 305 pci_iov_set_numvfs(dev, nr_virtfn); 306 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; 307 pci_cfg_access_lock(dev); 308 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 309 msleep(100); 310 pci_cfg_access_unlock(dev); 311 312 iov->initial_VFs = initial; 313 if (nr_virtfn < initial) 314 initial = nr_virtfn; 315 316 if ((retval = pcibios_sriov_enable(dev, initial))) { 317 dev_err(&dev->dev, "failure %d from pcibios_sriov_enable()\n", 318 retval); 319 return retval; 320 } 321 322 for (i = 0; i < initial; i++) { 323 rc = virtfn_add(dev, i, 0); 324 if (rc) 325 goto failed; 326 } 327 328 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); 329 iov->num_VFs = nr_virtfn; 330 331 return 0; 332 333 failed: 334 for (j = 0; j < i; j++) 335 virtfn_remove(dev, j, 0); 336 337 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 338 pci_cfg_access_lock(dev); 339 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 340 pci_iov_set_numvfs(dev, 0); 341 ssleep(1); 342 pci_cfg_access_unlock(dev); 343 344 if (iov->link != dev->devfn) 345 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 346 347 return rc; 348 } 349 350 int __weak pcibios_sriov_disable(struct pci_dev *pdev) 351 { 352 return 0; 353 } 354 355 static void sriov_disable(struct pci_dev *dev) 356 { 357 int i; 358 struct pci_sriov *iov = dev->sriov; 359 360 if (!iov->num_VFs) 361 return; 362 363 for (i = 0; i < iov->num_VFs; i++) 364 virtfn_remove(dev, i, 0); 365 366 pcibios_sriov_disable(dev); 367 368 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 369 pci_cfg_access_lock(dev); 370 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 371 ssleep(1); 372 pci_cfg_access_unlock(dev); 373 374 if (iov->link != dev->devfn) 375 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 376 377 iov->num_VFs = 0; 378 pci_iov_set_numvfs(dev, 0); 379 } 380 381 static int sriov_init(struct pci_dev *dev, int pos) 382 { 383 int i, bar64; 384 int rc; 385 int nres; 386 u32 pgsz; 387 u16 ctrl, total, offset, stride; 388 struct pci_sriov *iov; 389 struct resource *res; 390 struct pci_dev *pdev; 391 392 if (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_END && 393 pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) 394 return -ENODEV; 395 396 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); 397 if (ctrl & PCI_SRIOV_CTRL_VFE) { 398 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); 399 ssleep(1); 400 } 401 402 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); 403 if (!total) 404 return 0; 405 406 ctrl = 0; 407 list_for_each_entry(pdev, &dev->bus->devices, bus_list) 408 if (pdev->is_physfn) 409 goto found; 410 411 pdev = NULL; 412 if (pci_ari_enabled(dev->bus)) 413 ctrl |= PCI_SRIOV_CTRL_ARI; 414 415 found: 416 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); 417 pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, 0); 418 pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset); 419 pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride); 420 if (!offset || (total > 1 && !stride)) 421 return -EIO; 422 423 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); 424 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; 425 pgsz &= ~((1 << i) - 1); 426 if (!pgsz) 427 return -EIO; 428 429 pgsz &= ~(pgsz - 1); 430 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz); 431 432 iov = kzalloc(sizeof(*iov), GFP_KERNEL); 433 if (!iov) 434 return -ENOMEM; 435 436 nres = 0; 437 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 438 res = &dev->resource[i + PCI_IOV_RESOURCES]; 439 bar64 = __pci_read_base(dev, pci_bar_unknown, res, 440 pos + PCI_SRIOV_BAR + i * 4); 441 if (!res->flags) 442 continue; 443 if (resource_size(res) & (PAGE_SIZE - 1)) { 444 rc = -EIO; 445 goto failed; 446 } 447 iov->barsz[i] = resource_size(res); 448 res->end = res->start + resource_size(res) * total - 1; 449 dev_info(&dev->dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n", 450 i, res, i, total); 451 i += bar64; 452 nres++; 453 } 454 455 iov->pos = pos; 456 iov->nres = nres; 457 iov->ctrl = ctrl; 458 iov->total_VFs = total; 459 iov->offset = offset; 460 iov->stride = stride; 461 iov->pgsz = pgsz; 462 iov->self = dev; 463 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); 464 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); 465 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) 466 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link); 467 468 if (pdev) 469 iov->dev = pci_dev_get(pdev); 470 else 471 iov->dev = dev; 472 473 mutex_init(&iov->lock); 474 475 dev->sriov = iov; 476 dev->is_physfn = 1; 477 iov->max_VF_buses = virtfn_max_buses(dev); 478 479 return 0; 480 481 failed: 482 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 483 res = &dev->resource[i + PCI_IOV_RESOURCES]; 484 res->flags = 0; 485 } 486 487 kfree(iov); 488 return rc; 489 } 490 491 static void sriov_release(struct pci_dev *dev) 492 { 493 BUG_ON(dev->sriov->num_VFs); 494 495 if (dev != dev->sriov->dev) 496 pci_dev_put(dev->sriov->dev); 497 498 mutex_destroy(&dev->sriov->lock); 499 500 kfree(dev->sriov); 501 dev->sriov = NULL; 502 } 503 504 static void sriov_restore_state(struct pci_dev *dev) 505 { 506 int i; 507 u16 ctrl; 508 struct pci_sriov *iov = dev->sriov; 509 510 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); 511 if (ctrl & PCI_SRIOV_CTRL_VFE) 512 return; 513 514 for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) 515 pci_update_resource(dev, i); 516 517 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); 518 pci_iov_set_numvfs(dev, iov->num_VFs); 519 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 520 if (iov->ctrl & PCI_SRIOV_CTRL_VFE) 521 msleep(100); 522 } 523 524 /** 525 * pci_iov_init - initialize the IOV capability 526 * @dev: the PCI device 527 * 528 * Returns 0 on success, or negative on failure. 529 */ 530 int pci_iov_init(struct pci_dev *dev) 531 { 532 int pos; 533 534 if (!pci_is_pcie(dev)) 535 return -ENODEV; 536 537 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); 538 if (pos) 539 return sriov_init(dev, pos); 540 541 return -ENODEV; 542 } 543 544 /** 545 * pci_iov_release - release resources used by the IOV capability 546 * @dev: the PCI device 547 */ 548 void pci_iov_release(struct pci_dev *dev) 549 { 550 if (dev->is_physfn) 551 sriov_release(dev); 552 } 553 554 /** 555 * pci_iov_resource_bar - get position of the SR-IOV BAR 556 * @dev: the PCI device 557 * @resno: the resource number 558 * 559 * Returns position of the BAR encapsulated in the SR-IOV capability. 560 */ 561 int pci_iov_resource_bar(struct pci_dev *dev, int resno) 562 { 563 if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END) 564 return 0; 565 566 BUG_ON(!dev->is_physfn); 567 568 return dev->sriov->pos + PCI_SRIOV_BAR + 569 4 * (resno - PCI_IOV_RESOURCES); 570 } 571 572 resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev, 573 int resno) 574 { 575 return pci_iov_resource_size(dev, resno); 576 } 577 578 /** 579 * pci_sriov_resource_alignment - get resource alignment for VF BAR 580 * @dev: the PCI device 581 * @resno: the resource number 582 * 583 * Returns the alignment of the VF BAR found in the SR-IOV capability. 584 * This is not the same as the resource size which is defined as 585 * the VF BAR size multiplied by the number of VFs. The alignment 586 * is just the VF BAR size. 587 */ 588 resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno) 589 { 590 return pcibios_iov_resource_alignment(dev, resno); 591 } 592 593 /** 594 * pci_restore_iov_state - restore the state of the IOV capability 595 * @dev: the PCI device 596 */ 597 void pci_restore_iov_state(struct pci_dev *dev) 598 { 599 if (dev->is_physfn) 600 sriov_restore_state(dev); 601 } 602 603 /** 604 * pci_iov_bus_range - find bus range used by Virtual Function 605 * @bus: the PCI bus 606 * 607 * Returns max number of buses (exclude current one) used by Virtual 608 * Functions. 609 */ 610 int pci_iov_bus_range(struct pci_bus *bus) 611 { 612 int max = 0; 613 struct pci_dev *dev; 614 615 list_for_each_entry(dev, &bus->devices, bus_list) { 616 if (!dev->is_physfn) 617 continue; 618 if (dev->sriov->max_VF_buses > max) 619 max = dev->sriov->max_VF_buses; 620 } 621 622 return max ? max - bus->number : 0; 623 } 624 625 /** 626 * pci_enable_sriov - enable the SR-IOV capability 627 * @dev: the PCI device 628 * @nr_virtfn: number of virtual functions to enable 629 * 630 * Returns 0 on success, or negative on failure. 631 */ 632 int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) 633 { 634 might_sleep(); 635 636 if (!dev->is_physfn) 637 return -ENOSYS; 638 639 return sriov_enable(dev, nr_virtfn); 640 } 641 EXPORT_SYMBOL_GPL(pci_enable_sriov); 642 643 /** 644 * pci_disable_sriov - disable the SR-IOV capability 645 * @dev: the PCI device 646 */ 647 void pci_disable_sriov(struct pci_dev *dev) 648 { 649 might_sleep(); 650 651 if (!dev->is_physfn) 652 return; 653 654 sriov_disable(dev); 655 } 656 EXPORT_SYMBOL_GPL(pci_disable_sriov); 657 658 /** 659 * pci_num_vf - return number of VFs associated with a PF device_release_driver 660 * @dev: the PCI device 661 * 662 * Returns number of VFs, or 0 if SR-IOV is not enabled. 663 */ 664 int pci_num_vf(struct pci_dev *dev) 665 { 666 if (!dev->is_physfn) 667 return 0; 668 669 return dev->sriov->num_VFs; 670 } 671 EXPORT_SYMBOL_GPL(pci_num_vf); 672 673 /** 674 * pci_vfs_assigned - returns number of VFs are assigned to a guest 675 * @dev: the PCI device 676 * 677 * Returns number of VFs belonging to this device that are assigned to a guest. 678 * If device is not a physical function returns 0. 679 */ 680 int pci_vfs_assigned(struct pci_dev *dev) 681 { 682 struct pci_dev *vfdev; 683 unsigned int vfs_assigned = 0; 684 unsigned short dev_id; 685 686 /* only search if we are a PF */ 687 if (!dev->is_physfn) 688 return 0; 689 690 /* 691 * determine the device ID for the VFs, the vendor ID will be the 692 * same as the PF so there is no need to check for that one 693 */ 694 pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_VF_DID, &dev_id); 695 696 /* loop through all the VFs to see if we own any that are assigned */ 697 vfdev = pci_get_device(dev->vendor, dev_id, NULL); 698 while (vfdev) { 699 /* 700 * It is considered assigned if it is a virtual function with 701 * our dev as the physical function and the assigned bit is set 702 */ 703 if (vfdev->is_virtfn && (vfdev->physfn == dev) && 704 pci_is_dev_assigned(vfdev)) 705 vfs_assigned++; 706 707 vfdev = pci_get_device(dev->vendor, dev_id, vfdev); 708 } 709 710 return vfs_assigned; 711 } 712 EXPORT_SYMBOL_GPL(pci_vfs_assigned); 713 714 /** 715 * pci_sriov_set_totalvfs -- reduce the TotalVFs available 716 * @dev: the PCI PF device 717 * @numvfs: number that should be used for TotalVFs supported 718 * 719 * Should be called from PF driver's probe routine with 720 * device's mutex held. 721 * 722 * Returns 0 if PF is an SRIOV-capable device and 723 * value of numvfs valid. If not a PF return -ENOSYS; 724 * if numvfs is invalid return -EINVAL; 725 * if VFs already enabled, return -EBUSY. 726 */ 727 int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs) 728 { 729 if (!dev->is_physfn) 730 return -ENOSYS; 731 if (numvfs > dev->sriov->total_VFs) 732 return -EINVAL; 733 734 /* Shouldn't change if VFs already enabled */ 735 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE) 736 return -EBUSY; 737 else 738 dev->sriov->driver_max_VFs = numvfs; 739 740 return 0; 741 } 742 EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs); 743 744 /** 745 * pci_sriov_get_totalvfs -- get total VFs supported on this device 746 * @dev: the PCI PF device 747 * 748 * For a PCIe device with SRIOV support, return the PCIe 749 * SRIOV capability value of TotalVFs or the value of driver_max_VFs 750 * if the driver reduced it. Otherwise 0. 751 */ 752 int pci_sriov_get_totalvfs(struct pci_dev *dev) 753 { 754 if (!dev->is_physfn) 755 return 0; 756 757 if (dev->sriov->driver_max_VFs) 758 return dev->sriov->driver_max_VFs; 759 760 return dev->sriov->total_VFs; 761 } 762 EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs); 763