1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * PCI Express I/O Virtualization (IOV) support 4 * Single Root IOV 1.0 5 * Address Translation Service 1.0 6 * 7 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com> 8 */ 9 10 #include <linux/pci.h> 11 #include <linux/slab.h> 12 #include <linux/export.h> 13 #include <linux/string.h> 14 #include <linux/delay.h> 15 #include "pci.h" 16 17 #define VIRTFN_ID_LEN 16 18 19 int pci_iov_virtfn_bus(struct pci_dev *dev, int vf_id) 20 { 21 if (!dev->is_physfn) 22 return -EINVAL; 23 return dev->bus->number + ((dev->devfn + dev->sriov->offset + 24 dev->sriov->stride * vf_id) >> 8); 25 } 26 27 int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id) 28 { 29 if (!dev->is_physfn) 30 return -EINVAL; 31 return (dev->devfn + dev->sriov->offset + 32 dev->sriov->stride * vf_id) & 0xff; 33 } 34 EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn); 35 36 /* 37 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may 38 * change when NumVFs changes. 39 * 40 * Update iov->offset and iov->stride when NumVFs is written. 41 */ 42 static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn) 43 { 44 struct pci_sriov *iov = dev->sriov; 45 46 pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); 47 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset); 48 pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride); 49 } 50 51 /* 52 * The PF consumes one bus number. NumVFs, First VF Offset, and VF Stride 53 * determine how many additional bus numbers will be consumed by VFs. 54 * 55 * Iterate over all valid NumVFs, validate offset and stride, and calculate 56 * the maximum number of bus numbers that could ever be required. 57 */ 58 static int compute_max_vf_buses(struct pci_dev *dev) 59 { 60 struct pci_sriov *iov = dev->sriov; 61 int nr_virtfn, busnr, rc = 0; 62 63 for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) { 64 pci_iov_set_numvfs(dev, nr_virtfn); 65 if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) { 66 rc = -EIO; 67 goto out; 68 } 69 70 busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1); 71 if (busnr > iov->max_VF_buses) 72 iov->max_VF_buses = busnr; 73 } 74 75 out: 76 pci_iov_set_numvfs(dev, 0); 77 return rc; 78 } 79 80 static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) 81 { 82 struct pci_bus *child; 83 84 if (bus->number == busnr) 85 return bus; 86 87 child = pci_find_bus(pci_domain_nr(bus), busnr); 88 if (child) 89 return child; 90 91 child = pci_add_new_bus(bus, NULL, busnr); 92 if (!child) 93 return NULL; 94 95 pci_bus_insert_busn_res(child, busnr, busnr); 96 97 return child; 98 } 99 100 static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) 101 { 102 if (physbus != virtbus && list_empty(&virtbus->devices)) 103 pci_remove_bus(virtbus); 104 } 105 106 resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno) 107 { 108 if (!dev->is_physfn) 109 return 0; 110 111 return dev->sriov->barsz[resno - PCI_IOV_RESOURCES]; 112 } 113 114 static void pci_read_vf_config_common(struct pci_dev *virtfn) 115 { 116 struct pci_dev *physfn = virtfn->physfn; 117 118 /* 119 * Some config registers are the same across all associated VFs. 120 * Read them once from VF0 so we can skip reading them from the 121 * other VFs. 122 * 123 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to 124 * have the same Revision ID and Subsystem ID, but we assume they 125 * do. 126 */ 127 pci_read_config_dword(virtfn, PCI_CLASS_REVISION, 128 &physfn->sriov->class); 129 pci_read_config_byte(virtfn, PCI_HEADER_TYPE, 130 &physfn->sriov->hdr_type); 131 pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID, 132 &physfn->sriov->subsystem_vendor); 133 pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID, 134 &physfn->sriov->subsystem_device); 135 } 136 137 int pci_iov_sysfs_link(struct pci_dev *dev, 138 struct pci_dev *virtfn, int id) 139 { 140 char buf[VIRTFN_ID_LEN]; 141 int rc; 142 143 sprintf(buf, "virtfn%u", id); 144 rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); 145 if (rc) 146 goto failed; 147 rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); 148 if (rc) 149 goto failed1; 150 151 kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); 152 153 return 0; 154 155 failed1: 156 sysfs_remove_link(&dev->dev.kobj, buf); 157 failed: 158 return rc; 159 } 160 161 #ifdef CONFIG_PCI_MSI 162 static ssize_t sriov_vf_total_msix_show(struct device *dev, 163 struct device_attribute *attr, 164 char *buf) 165 { 166 struct pci_dev *pdev = to_pci_dev(dev); 167 u32 vf_total_msix = 0; 168 169 device_lock(dev); 170 if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix) 171 goto unlock; 172 173 vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev); 174 unlock: 175 device_unlock(dev); 176 return sysfs_emit(buf, "%u\n", vf_total_msix); 177 } 178 static DEVICE_ATTR_RO(sriov_vf_total_msix); 179 180 static ssize_t sriov_vf_msix_count_store(struct device *dev, 181 struct device_attribute *attr, 182 const char *buf, size_t count) 183 { 184 struct pci_dev *vf_dev = to_pci_dev(dev); 185 struct pci_dev *pdev = pci_physfn(vf_dev); 186 int val, ret; 187 188 ret = kstrtoint(buf, 0, &val); 189 if (ret) 190 return ret; 191 192 if (val < 0) 193 return -EINVAL; 194 195 device_lock(&pdev->dev); 196 if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) { 197 ret = -EOPNOTSUPP; 198 goto err_pdev; 199 } 200 201 device_lock(&vf_dev->dev); 202 if (vf_dev->driver) { 203 /* 204 * A driver is already attached to this VF and has configured 205 * itself based on the current MSI-X vector count. Changing 206 * the vector size could mess up the driver, so block it. 207 */ 208 ret = -EBUSY; 209 goto err_dev; 210 } 211 212 ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val); 213 214 err_dev: 215 device_unlock(&vf_dev->dev); 216 err_pdev: 217 device_unlock(&pdev->dev); 218 return ret ? : count; 219 } 220 static DEVICE_ATTR_WO(sriov_vf_msix_count); 221 #endif 222 223 static struct attribute *sriov_vf_dev_attrs[] = { 224 #ifdef CONFIG_PCI_MSI 225 &dev_attr_sriov_vf_msix_count.attr, 226 #endif 227 NULL, 228 }; 229 230 static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj, 231 struct attribute *a, int n) 232 { 233 struct device *dev = kobj_to_dev(kobj); 234 struct pci_dev *pdev = to_pci_dev(dev); 235 236 if (!pdev->is_virtfn) 237 return 0; 238 239 return a->mode; 240 } 241 242 const struct attribute_group sriov_vf_dev_attr_group = { 243 .attrs = sriov_vf_dev_attrs, 244 .is_visible = sriov_vf_attrs_are_visible, 245 }; 246 247 int pci_iov_add_virtfn(struct pci_dev *dev, int id) 248 { 249 int i; 250 int rc = -ENOMEM; 251 u64 size; 252 struct pci_dev *virtfn; 253 struct resource *res; 254 struct pci_sriov *iov = dev->sriov; 255 struct pci_bus *bus; 256 257 bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id)); 258 if (!bus) 259 goto failed; 260 261 virtfn = pci_alloc_dev(bus); 262 if (!virtfn) 263 goto failed0; 264 265 virtfn->devfn = pci_iov_virtfn_devfn(dev, id); 266 virtfn->vendor = dev->vendor; 267 virtfn->device = iov->vf_device; 268 virtfn->is_virtfn = 1; 269 virtfn->physfn = pci_dev_get(dev); 270 virtfn->no_command_memory = 1; 271 272 if (id == 0) 273 pci_read_vf_config_common(virtfn); 274 275 rc = pci_setup_device(virtfn); 276 if (rc) 277 goto failed1; 278 279 virtfn->dev.parent = dev->dev.parent; 280 virtfn->multifunction = 0; 281 282 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 283 res = &dev->resource[i + PCI_IOV_RESOURCES]; 284 if (!res->parent) 285 continue; 286 virtfn->resource[i].name = pci_name(virtfn); 287 virtfn->resource[i].flags = res->flags; 288 size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES); 289 virtfn->resource[i].start = res->start + size * id; 290 virtfn->resource[i].end = virtfn->resource[i].start + size - 1; 291 rc = request_resource(res, &virtfn->resource[i]); 292 BUG_ON(rc); 293 } 294 295 pci_device_add(virtfn, virtfn->bus); 296 rc = pci_iov_sysfs_link(dev, virtfn, id); 297 if (rc) 298 goto failed1; 299 300 pci_bus_add_device(virtfn); 301 302 return 0; 303 304 failed1: 305 pci_stop_and_remove_bus_device(virtfn); 306 pci_dev_put(dev); 307 failed0: 308 virtfn_remove_bus(dev->bus, bus); 309 failed: 310 311 return rc; 312 } 313 314 void pci_iov_remove_virtfn(struct pci_dev *dev, int id) 315 { 316 char buf[VIRTFN_ID_LEN]; 317 struct pci_dev *virtfn; 318 319 virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), 320 pci_iov_virtfn_bus(dev, id), 321 pci_iov_virtfn_devfn(dev, id)); 322 if (!virtfn) 323 return; 324 325 sprintf(buf, "virtfn%u", id); 326 sysfs_remove_link(&dev->dev.kobj, buf); 327 /* 328 * pci_stop_dev() could have been called for this virtfn already, 329 * so the directory for the virtfn may have been removed before. 330 * Double check to avoid spurious sysfs warnings. 331 */ 332 if (virtfn->dev.kobj.sd) 333 sysfs_remove_link(&virtfn->dev.kobj, "physfn"); 334 335 pci_stop_and_remove_bus_device(virtfn); 336 virtfn_remove_bus(dev->bus, virtfn->bus); 337 338 /* balance pci_get_domain_bus_and_slot() */ 339 pci_dev_put(virtfn); 340 pci_dev_put(dev); 341 } 342 343 static ssize_t sriov_totalvfs_show(struct device *dev, 344 struct device_attribute *attr, 345 char *buf) 346 { 347 struct pci_dev *pdev = to_pci_dev(dev); 348 349 return sprintf(buf, "%u\n", pci_sriov_get_totalvfs(pdev)); 350 } 351 352 static ssize_t sriov_numvfs_show(struct device *dev, 353 struct device_attribute *attr, 354 char *buf) 355 { 356 struct pci_dev *pdev = to_pci_dev(dev); 357 u16 num_vfs; 358 359 /* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */ 360 device_lock(&pdev->dev); 361 num_vfs = pdev->sriov->num_VFs; 362 device_unlock(&pdev->dev); 363 364 return sprintf(buf, "%u\n", num_vfs); 365 } 366 367 /* 368 * num_vfs > 0; number of VFs to enable 369 * num_vfs = 0; disable all VFs 370 * 371 * Note: SRIOV spec does not allow partial VF 372 * disable, so it's all or none. 373 */ 374 static ssize_t sriov_numvfs_store(struct device *dev, 375 struct device_attribute *attr, 376 const char *buf, size_t count) 377 { 378 struct pci_dev *pdev = to_pci_dev(dev); 379 int ret; 380 u16 num_vfs; 381 382 ret = kstrtou16(buf, 0, &num_vfs); 383 if (ret < 0) 384 return ret; 385 386 if (num_vfs > pci_sriov_get_totalvfs(pdev)) 387 return -ERANGE; 388 389 device_lock(&pdev->dev); 390 391 if (num_vfs == pdev->sriov->num_VFs) 392 goto exit; 393 394 /* is PF driver loaded w/callback */ 395 if (!pdev->driver || !pdev->driver->sriov_configure) { 396 pci_info(pdev, "Driver does not support SRIOV configuration via sysfs\n"); 397 ret = -ENOENT; 398 goto exit; 399 } 400 401 if (num_vfs == 0) { 402 /* disable VFs */ 403 ret = pdev->driver->sriov_configure(pdev, 0); 404 goto exit; 405 } 406 407 /* enable VFs */ 408 if (pdev->sriov->num_VFs) { 409 pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n", 410 pdev->sriov->num_VFs, num_vfs); 411 ret = -EBUSY; 412 goto exit; 413 } 414 415 ret = pdev->driver->sriov_configure(pdev, num_vfs); 416 if (ret < 0) 417 goto exit; 418 419 if (ret != num_vfs) 420 pci_warn(pdev, "%d VFs requested; only %d enabled\n", 421 num_vfs, ret); 422 423 exit: 424 device_unlock(&pdev->dev); 425 426 if (ret < 0) 427 return ret; 428 429 return count; 430 } 431 432 static ssize_t sriov_offset_show(struct device *dev, 433 struct device_attribute *attr, 434 char *buf) 435 { 436 struct pci_dev *pdev = to_pci_dev(dev); 437 438 return sprintf(buf, "%u\n", pdev->sriov->offset); 439 } 440 441 static ssize_t sriov_stride_show(struct device *dev, 442 struct device_attribute *attr, 443 char *buf) 444 { 445 struct pci_dev *pdev = to_pci_dev(dev); 446 447 return sprintf(buf, "%u\n", pdev->sriov->stride); 448 } 449 450 static ssize_t sriov_vf_device_show(struct device *dev, 451 struct device_attribute *attr, 452 char *buf) 453 { 454 struct pci_dev *pdev = to_pci_dev(dev); 455 456 return sprintf(buf, "%x\n", pdev->sriov->vf_device); 457 } 458 459 static ssize_t sriov_drivers_autoprobe_show(struct device *dev, 460 struct device_attribute *attr, 461 char *buf) 462 { 463 struct pci_dev *pdev = to_pci_dev(dev); 464 465 return sprintf(buf, "%u\n", pdev->sriov->drivers_autoprobe); 466 } 467 468 static ssize_t sriov_drivers_autoprobe_store(struct device *dev, 469 struct device_attribute *attr, 470 const char *buf, size_t count) 471 { 472 struct pci_dev *pdev = to_pci_dev(dev); 473 bool drivers_autoprobe; 474 475 if (kstrtobool(buf, &drivers_autoprobe) < 0) 476 return -EINVAL; 477 478 pdev->sriov->drivers_autoprobe = drivers_autoprobe; 479 480 return count; 481 } 482 483 static DEVICE_ATTR_RO(sriov_totalvfs); 484 static DEVICE_ATTR_RW(sriov_numvfs); 485 static DEVICE_ATTR_RO(sriov_offset); 486 static DEVICE_ATTR_RO(sriov_stride); 487 static DEVICE_ATTR_RO(sriov_vf_device); 488 static DEVICE_ATTR_RW(sriov_drivers_autoprobe); 489 490 static struct attribute *sriov_pf_dev_attrs[] = { 491 &dev_attr_sriov_totalvfs.attr, 492 &dev_attr_sriov_numvfs.attr, 493 &dev_attr_sriov_offset.attr, 494 &dev_attr_sriov_stride.attr, 495 &dev_attr_sriov_vf_device.attr, 496 &dev_attr_sriov_drivers_autoprobe.attr, 497 #ifdef CONFIG_PCI_MSI 498 &dev_attr_sriov_vf_total_msix.attr, 499 #endif 500 NULL, 501 }; 502 503 static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj, 504 struct attribute *a, int n) 505 { 506 struct device *dev = kobj_to_dev(kobj); 507 508 if (!dev_is_pf(dev)) 509 return 0; 510 511 return a->mode; 512 } 513 514 const struct attribute_group sriov_pf_dev_attr_group = { 515 .attrs = sriov_pf_dev_attrs, 516 .is_visible = sriov_pf_attrs_are_visible, 517 }; 518 519 int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs) 520 { 521 return 0; 522 } 523 524 int __weak pcibios_sriov_disable(struct pci_dev *pdev) 525 { 526 return 0; 527 } 528 529 static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs) 530 { 531 unsigned int i; 532 int rc; 533 534 if (dev->no_vf_scan) 535 return 0; 536 537 for (i = 0; i < num_vfs; i++) { 538 rc = pci_iov_add_virtfn(dev, i); 539 if (rc) 540 goto failed; 541 } 542 return 0; 543 failed: 544 while (i--) 545 pci_iov_remove_virtfn(dev, i); 546 547 return rc; 548 } 549 550 static int sriov_enable(struct pci_dev *dev, int nr_virtfn) 551 { 552 int rc; 553 int i; 554 int nres; 555 u16 initial; 556 struct resource *res; 557 struct pci_dev *pdev; 558 struct pci_sriov *iov = dev->sriov; 559 int bars = 0; 560 int bus; 561 562 if (!nr_virtfn) 563 return 0; 564 565 if (iov->num_VFs) 566 return -EINVAL; 567 568 pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); 569 if (initial > iov->total_VFs || 570 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs))) 571 return -EIO; 572 573 if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs || 574 (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) 575 return -EINVAL; 576 577 nres = 0; 578 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 579 bars |= (1 << (i + PCI_IOV_RESOURCES)); 580 res = &dev->resource[i + PCI_IOV_RESOURCES]; 581 if (res->parent) 582 nres++; 583 } 584 if (nres != iov->nres) { 585 pci_err(dev, "not enough MMIO resources for SR-IOV\n"); 586 return -ENOMEM; 587 } 588 589 bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1); 590 if (bus > dev->bus->busn_res.end) { 591 pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n", 592 nr_virtfn, bus, &dev->bus->busn_res); 593 return -ENOMEM; 594 } 595 596 if (pci_enable_resources(dev, bars)) { 597 pci_err(dev, "SR-IOV: IOV BARS not allocated\n"); 598 return -ENOMEM; 599 } 600 601 if (iov->link != dev->devfn) { 602 pdev = pci_get_slot(dev->bus, iov->link); 603 if (!pdev) 604 return -ENODEV; 605 606 if (!pdev->is_physfn) { 607 pci_dev_put(pdev); 608 return -ENOSYS; 609 } 610 611 rc = sysfs_create_link(&dev->dev.kobj, 612 &pdev->dev.kobj, "dep_link"); 613 pci_dev_put(pdev); 614 if (rc) 615 return rc; 616 } 617 618 iov->initial_VFs = initial; 619 if (nr_virtfn < initial) 620 initial = nr_virtfn; 621 622 rc = pcibios_sriov_enable(dev, initial); 623 if (rc) { 624 pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc); 625 goto err_pcibios; 626 } 627 628 pci_iov_set_numvfs(dev, nr_virtfn); 629 iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; 630 pci_cfg_access_lock(dev); 631 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 632 msleep(100); 633 pci_cfg_access_unlock(dev); 634 635 rc = sriov_add_vfs(dev, initial); 636 if (rc) 637 goto err_pcibios; 638 639 kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); 640 iov->num_VFs = nr_virtfn; 641 642 return 0; 643 644 err_pcibios: 645 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 646 pci_cfg_access_lock(dev); 647 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 648 ssleep(1); 649 pci_cfg_access_unlock(dev); 650 651 pcibios_sriov_disable(dev); 652 653 if (iov->link != dev->devfn) 654 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 655 656 pci_iov_set_numvfs(dev, 0); 657 return rc; 658 } 659 660 static void sriov_del_vfs(struct pci_dev *dev) 661 { 662 struct pci_sriov *iov = dev->sriov; 663 int i; 664 665 for (i = 0; i < iov->num_VFs; i++) 666 pci_iov_remove_virtfn(dev, i); 667 } 668 669 static void sriov_disable(struct pci_dev *dev) 670 { 671 struct pci_sriov *iov = dev->sriov; 672 673 if (!iov->num_VFs) 674 return; 675 676 sriov_del_vfs(dev); 677 iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); 678 pci_cfg_access_lock(dev); 679 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 680 ssleep(1); 681 pci_cfg_access_unlock(dev); 682 683 pcibios_sriov_disable(dev); 684 685 if (iov->link != dev->devfn) 686 sysfs_remove_link(&dev->dev.kobj, "dep_link"); 687 688 iov->num_VFs = 0; 689 pci_iov_set_numvfs(dev, 0); 690 } 691 692 static int sriov_init(struct pci_dev *dev, int pos) 693 { 694 int i, bar64; 695 int rc; 696 int nres; 697 u32 pgsz; 698 u16 ctrl, total; 699 struct pci_sriov *iov; 700 struct resource *res; 701 struct pci_dev *pdev; 702 703 pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); 704 if (ctrl & PCI_SRIOV_CTRL_VFE) { 705 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); 706 ssleep(1); 707 } 708 709 ctrl = 0; 710 list_for_each_entry(pdev, &dev->bus->devices, bus_list) 711 if (pdev->is_physfn) 712 goto found; 713 714 pdev = NULL; 715 if (pci_ari_enabled(dev->bus)) 716 ctrl |= PCI_SRIOV_CTRL_ARI; 717 718 found: 719 pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); 720 721 pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); 722 if (!total) 723 return 0; 724 725 pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); 726 i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; 727 pgsz &= ~((1 << i) - 1); 728 if (!pgsz) 729 return -EIO; 730 731 pgsz &= ~(pgsz - 1); 732 pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz); 733 734 iov = kzalloc(sizeof(*iov), GFP_KERNEL); 735 if (!iov) 736 return -ENOMEM; 737 738 nres = 0; 739 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 740 res = &dev->resource[i + PCI_IOV_RESOURCES]; 741 /* 742 * If it is already FIXED, don't change it, something 743 * (perhaps EA or header fixups) wants it this way. 744 */ 745 if (res->flags & IORESOURCE_PCI_FIXED) 746 bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0; 747 else 748 bar64 = __pci_read_base(dev, pci_bar_unknown, res, 749 pos + PCI_SRIOV_BAR + i * 4); 750 if (!res->flags) 751 continue; 752 if (resource_size(res) & (PAGE_SIZE - 1)) { 753 rc = -EIO; 754 goto failed; 755 } 756 iov->barsz[i] = resource_size(res); 757 res->end = res->start + resource_size(res) * total - 1; 758 pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n", 759 i, res, i, total); 760 i += bar64; 761 nres++; 762 } 763 764 iov->pos = pos; 765 iov->nres = nres; 766 iov->ctrl = ctrl; 767 iov->total_VFs = total; 768 iov->driver_max_VFs = total; 769 pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device); 770 iov->pgsz = pgsz; 771 iov->self = dev; 772 iov->drivers_autoprobe = true; 773 pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); 774 pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); 775 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) 776 iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link); 777 778 if (pdev) 779 iov->dev = pci_dev_get(pdev); 780 else 781 iov->dev = dev; 782 783 dev->sriov = iov; 784 dev->is_physfn = 1; 785 rc = compute_max_vf_buses(dev); 786 if (rc) 787 goto fail_max_buses; 788 789 return 0; 790 791 fail_max_buses: 792 dev->sriov = NULL; 793 dev->is_physfn = 0; 794 failed: 795 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { 796 res = &dev->resource[i + PCI_IOV_RESOURCES]; 797 res->flags = 0; 798 } 799 800 kfree(iov); 801 return rc; 802 } 803 804 static void sriov_release(struct pci_dev *dev) 805 { 806 BUG_ON(dev->sriov->num_VFs); 807 808 if (dev != dev->sriov->dev) 809 pci_dev_put(dev->sriov->dev); 810 811 kfree(dev->sriov); 812 dev->sriov = NULL; 813 } 814 815 static void sriov_restore_state(struct pci_dev *dev) 816 { 817 int i; 818 u16 ctrl; 819 struct pci_sriov *iov = dev->sriov; 820 821 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); 822 if (ctrl & PCI_SRIOV_CTRL_VFE) 823 return; 824 825 /* 826 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because 827 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI. 828 */ 829 ctrl &= ~PCI_SRIOV_CTRL_ARI; 830 ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI; 831 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl); 832 833 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) 834 pci_update_resource(dev, i + PCI_IOV_RESOURCES); 835 836 pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); 837 pci_iov_set_numvfs(dev, iov->num_VFs); 838 pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); 839 if (iov->ctrl & PCI_SRIOV_CTRL_VFE) 840 msleep(100); 841 } 842 843 /** 844 * pci_iov_init - initialize the IOV capability 845 * @dev: the PCI device 846 * 847 * Returns 0 on success, or negative on failure. 848 */ 849 int pci_iov_init(struct pci_dev *dev) 850 { 851 int pos; 852 853 if (!pci_is_pcie(dev)) 854 return -ENODEV; 855 856 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); 857 if (pos) 858 return sriov_init(dev, pos); 859 860 return -ENODEV; 861 } 862 863 /** 864 * pci_iov_release - release resources used by the IOV capability 865 * @dev: the PCI device 866 */ 867 void pci_iov_release(struct pci_dev *dev) 868 { 869 if (dev->is_physfn) 870 sriov_release(dev); 871 } 872 873 /** 874 * pci_iov_remove - clean up SR-IOV state after PF driver is detached 875 * @dev: the PCI device 876 */ 877 void pci_iov_remove(struct pci_dev *dev) 878 { 879 struct pci_sriov *iov = dev->sriov; 880 881 if (!dev->is_physfn) 882 return; 883 884 iov->driver_max_VFs = iov->total_VFs; 885 if (iov->num_VFs) 886 pci_warn(dev, "driver left SR-IOV enabled after remove\n"); 887 } 888 889 /** 890 * pci_iov_update_resource - update a VF BAR 891 * @dev: the PCI device 892 * @resno: the resource number 893 * 894 * Update a VF BAR in the SR-IOV capability of a PF. 895 */ 896 void pci_iov_update_resource(struct pci_dev *dev, int resno) 897 { 898 struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL; 899 struct resource *res = dev->resource + resno; 900 int vf_bar = resno - PCI_IOV_RESOURCES; 901 struct pci_bus_region region; 902 u16 cmd; 903 u32 new; 904 int reg; 905 906 /* 907 * The generic pci_restore_bars() path calls this for all devices, 908 * including VFs and non-SR-IOV devices. If this is not a PF, we 909 * have nothing to do. 910 */ 911 if (!iov) 912 return; 913 914 pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd); 915 if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) { 916 dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n", 917 vf_bar, res); 918 return; 919 } 920 921 /* 922 * Ignore unimplemented BARs, unused resource slots for 64-bit 923 * BARs, and non-movable resources, e.g., those described via 924 * Enhanced Allocation. 925 */ 926 if (!res->flags) 927 return; 928 929 if (res->flags & IORESOURCE_UNSET) 930 return; 931 932 if (res->flags & IORESOURCE_PCI_FIXED) 933 return; 934 935 pcibios_resource_to_bus(dev->bus, ®ion, res); 936 new = region.start; 937 new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK; 938 939 reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar; 940 pci_write_config_dword(dev, reg, new); 941 if (res->flags & IORESOURCE_MEM_64) { 942 new = region.start >> 16 >> 16; 943 pci_write_config_dword(dev, reg + 4, new); 944 } 945 } 946 947 resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev, 948 int resno) 949 { 950 return pci_iov_resource_size(dev, resno); 951 } 952 953 /** 954 * pci_sriov_resource_alignment - get resource alignment for VF BAR 955 * @dev: the PCI device 956 * @resno: the resource number 957 * 958 * Returns the alignment of the VF BAR found in the SR-IOV capability. 959 * This is not the same as the resource size which is defined as 960 * the VF BAR size multiplied by the number of VFs. The alignment 961 * is just the VF BAR size. 962 */ 963 resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno) 964 { 965 return pcibios_iov_resource_alignment(dev, resno); 966 } 967 968 /** 969 * pci_restore_iov_state - restore the state of the IOV capability 970 * @dev: the PCI device 971 */ 972 void pci_restore_iov_state(struct pci_dev *dev) 973 { 974 if (dev->is_physfn) 975 sriov_restore_state(dev); 976 } 977 978 /** 979 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs 980 * @dev: the PCI device 981 * @auto_probe: set VF drivers auto probe flag 982 */ 983 void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe) 984 { 985 if (dev->is_physfn) 986 dev->sriov->drivers_autoprobe = auto_probe; 987 } 988 989 /** 990 * pci_iov_bus_range - find bus range used by Virtual Function 991 * @bus: the PCI bus 992 * 993 * Returns max number of buses (exclude current one) used by Virtual 994 * Functions. 995 */ 996 int pci_iov_bus_range(struct pci_bus *bus) 997 { 998 int max = 0; 999 struct pci_dev *dev; 1000 1001 list_for_each_entry(dev, &bus->devices, bus_list) { 1002 if (!dev->is_physfn) 1003 continue; 1004 if (dev->sriov->max_VF_buses > max) 1005 max = dev->sriov->max_VF_buses; 1006 } 1007 1008 return max ? max - bus->number : 0; 1009 } 1010 1011 /** 1012 * pci_enable_sriov - enable the SR-IOV capability 1013 * @dev: the PCI device 1014 * @nr_virtfn: number of virtual functions to enable 1015 * 1016 * Returns 0 on success, or negative on failure. 1017 */ 1018 int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) 1019 { 1020 might_sleep(); 1021 1022 if (!dev->is_physfn) 1023 return -ENOSYS; 1024 1025 return sriov_enable(dev, nr_virtfn); 1026 } 1027 EXPORT_SYMBOL_GPL(pci_enable_sriov); 1028 1029 /** 1030 * pci_disable_sriov - disable the SR-IOV capability 1031 * @dev: the PCI device 1032 */ 1033 void pci_disable_sriov(struct pci_dev *dev) 1034 { 1035 might_sleep(); 1036 1037 if (!dev->is_physfn) 1038 return; 1039 1040 sriov_disable(dev); 1041 } 1042 EXPORT_SYMBOL_GPL(pci_disable_sriov); 1043 1044 /** 1045 * pci_num_vf - return number of VFs associated with a PF device_release_driver 1046 * @dev: the PCI device 1047 * 1048 * Returns number of VFs, or 0 if SR-IOV is not enabled. 1049 */ 1050 int pci_num_vf(struct pci_dev *dev) 1051 { 1052 if (!dev->is_physfn) 1053 return 0; 1054 1055 return dev->sriov->num_VFs; 1056 } 1057 EXPORT_SYMBOL_GPL(pci_num_vf); 1058 1059 /** 1060 * pci_vfs_assigned - returns number of VFs are assigned to a guest 1061 * @dev: the PCI device 1062 * 1063 * Returns number of VFs belonging to this device that are assigned to a guest. 1064 * If device is not a physical function returns 0. 1065 */ 1066 int pci_vfs_assigned(struct pci_dev *dev) 1067 { 1068 struct pci_dev *vfdev; 1069 unsigned int vfs_assigned = 0; 1070 unsigned short dev_id; 1071 1072 /* only search if we are a PF */ 1073 if (!dev->is_physfn) 1074 return 0; 1075 1076 /* 1077 * determine the device ID for the VFs, the vendor ID will be the 1078 * same as the PF so there is no need to check for that one 1079 */ 1080 dev_id = dev->sriov->vf_device; 1081 1082 /* loop through all the VFs to see if we own any that are assigned */ 1083 vfdev = pci_get_device(dev->vendor, dev_id, NULL); 1084 while (vfdev) { 1085 /* 1086 * It is considered assigned if it is a virtual function with 1087 * our dev as the physical function and the assigned bit is set 1088 */ 1089 if (vfdev->is_virtfn && (vfdev->physfn == dev) && 1090 pci_is_dev_assigned(vfdev)) 1091 vfs_assigned++; 1092 1093 vfdev = pci_get_device(dev->vendor, dev_id, vfdev); 1094 } 1095 1096 return vfs_assigned; 1097 } 1098 EXPORT_SYMBOL_GPL(pci_vfs_assigned); 1099 1100 /** 1101 * pci_sriov_set_totalvfs -- reduce the TotalVFs available 1102 * @dev: the PCI PF device 1103 * @numvfs: number that should be used for TotalVFs supported 1104 * 1105 * Should be called from PF driver's probe routine with 1106 * device's mutex held. 1107 * 1108 * Returns 0 if PF is an SRIOV-capable device and 1109 * value of numvfs valid. If not a PF return -ENOSYS; 1110 * if numvfs is invalid return -EINVAL; 1111 * if VFs already enabled, return -EBUSY. 1112 */ 1113 int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs) 1114 { 1115 if (!dev->is_physfn) 1116 return -ENOSYS; 1117 1118 if (numvfs > dev->sriov->total_VFs) 1119 return -EINVAL; 1120 1121 /* Shouldn't change if VFs already enabled */ 1122 if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE) 1123 return -EBUSY; 1124 1125 dev->sriov->driver_max_VFs = numvfs; 1126 return 0; 1127 } 1128 EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs); 1129 1130 /** 1131 * pci_sriov_get_totalvfs -- get total VFs supported on this device 1132 * @dev: the PCI PF device 1133 * 1134 * For a PCIe device with SRIOV support, return the PCIe 1135 * SRIOV capability value of TotalVFs or the value of driver_max_VFs 1136 * if the driver reduced it. Otherwise 0. 1137 */ 1138 int pci_sriov_get_totalvfs(struct pci_dev *dev) 1139 { 1140 if (!dev->is_physfn) 1141 return 0; 1142 1143 return dev->sriov->driver_max_VFs; 1144 } 1145 EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs); 1146 1147 /** 1148 * pci_sriov_configure_simple - helper to configure SR-IOV 1149 * @dev: the PCI device 1150 * @nr_virtfn: number of virtual functions to enable, 0 to disable 1151 * 1152 * Enable or disable SR-IOV for devices that don't require any PF setup 1153 * before enabling SR-IOV. Return value is negative on error, or number of 1154 * VFs allocated on success. 1155 */ 1156 int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn) 1157 { 1158 int rc; 1159 1160 might_sleep(); 1161 1162 if (!dev->is_physfn) 1163 return -ENODEV; 1164 1165 if (pci_vfs_assigned(dev)) { 1166 pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n"); 1167 return -EPERM; 1168 } 1169 1170 if (nr_virtfn == 0) { 1171 sriov_disable(dev); 1172 return 0; 1173 } 1174 1175 rc = sriov_enable(dev, nr_virtfn); 1176 if (rc < 0) 1177 return rc; 1178 1179 return nr_virtfn; 1180 } 1181 EXPORT_SYMBOL_GPL(pci_sriov_configure_simple); 1182