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v6.13.7
   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	17	/* "virtfn%u\0" for 2^32 - 1 */
  18
  19int 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
  27int 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}
  34EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn);
  35
  36int pci_iov_vf_id(struct pci_dev *dev)
  37{
  38	struct pci_dev *pf;
  39
  40	if (!dev->is_virtfn)
  41		return -EINVAL;
  42
  43	pf = pci_physfn(dev);
  44	return (pci_dev_id(dev) - (pci_dev_id(pf) + pf->sriov->offset)) /
  45	       pf->sriov->stride;
  46}
  47EXPORT_SYMBOL_GPL(pci_iov_vf_id);
  48
  49/**
  50 * pci_iov_get_pf_drvdata - Return the drvdata of a PF
  51 * @dev: VF pci_dev
  52 * @pf_driver: Device driver required to own the PF
  53 *
  54 * This must be called from a context that ensures that a VF driver is attached.
  55 * The value returned is invalid once the VF driver completes its remove()
  56 * callback.
  57 *
  58 * Locking is achieved by the driver core. A VF driver cannot be probed until
  59 * pci_enable_sriov() is called and pci_disable_sriov() does not return until
  60 * all VF drivers have completed their remove().
  61 *
  62 * The PF driver must call pci_disable_sriov() before it begins to destroy the
  63 * drvdata.
  64 */
  65void *pci_iov_get_pf_drvdata(struct pci_dev *dev, struct pci_driver *pf_driver)
  66{
  67	struct pci_dev *pf_dev;
  68
  69	if (!dev->is_virtfn)
  70		return ERR_PTR(-EINVAL);
  71	pf_dev = dev->physfn;
  72	if (pf_dev->driver != pf_driver)
  73		return ERR_PTR(-EINVAL);
  74	return pci_get_drvdata(pf_dev);
  75}
  76EXPORT_SYMBOL_GPL(pci_iov_get_pf_drvdata);
  77
  78/*
  79 * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may
  80 * change when NumVFs changes.
  81 *
  82 * Update iov->offset and iov->stride when NumVFs is written.
  83 */
  84static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn)
  85{
  86	struct pci_sriov *iov = dev->sriov;
  87
  88	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
  89	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset);
  90	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride);
  91}
  92
  93/*
  94 * The PF consumes one bus number.  NumVFs, First VF Offset, and VF Stride
  95 * determine how many additional bus numbers will be consumed by VFs.
  96 *
  97 * Iterate over all valid NumVFs, validate offset and stride, and calculate
  98 * the maximum number of bus numbers that could ever be required.
  99 */
 100static int compute_max_vf_buses(struct pci_dev *dev)
 101{
 102	struct pci_sriov *iov = dev->sriov;
 103	int nr_virtfn, busnr, rc = 0;
 104
 105	for (nr_virtfn = iov->total_VFs; nr_virtfn; nr_virtfn--) {
 106		pci_iov_set_numvfs(dev, nr_virtfn);
 107		if (!iov->offset || (nr_virtfn > 1 && !iov->stride)) {
 108			rc = -EIO;
 109			goto out;
 110		}
 111
 112		busnr = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
 113		if (busnr > iov->max_VF_buses)
 114			iov->max_VF_buses = busnr;
 115	}
 116
 117out:
 118	pci_iov_set_numvfs(dev, 0);
 119	return rc;
 120}
 121
 122static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
 123{
 124	struct pci_bus *child;
 125
 126	if (bus->number == busnr)
 127		return bus;
 128
 129	child = pci_find_bus(pci_domain_nr(bus), busnr);
 130	if (child)
 131		return child;
 132
 133	child = pci_add_new_bus(bus, NULL, busnr);
 134	if (!child)
 135		return NULL;
 136
 137	pci_bus_insert_busn_res(child, busnr, busnr);
 138
 139	return child;
 140}
 141
 142static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus)
 143{
 144	if (physbus != virtbus && list_empty(&virtbus->devices))
 145		pci_remove_bus(virtbus);
 146}
 147
 148resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
 149{
 150	if (!dev->is_physfn)
 151		return 0;
 152
 153	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
 154}
 155
 156static void pci_read_vf_config_common(struct pci_dev *virtfn)
 157{
 158	struct pci_dev *physfn = virtfn->physfn;
 159
 160	/*
 161	 * Some config registers are the same across all associated VFs.
 162	 * Read them once from VF0 so we can skip reading them from the
 163	 * other VFs.
 164	 *
 165	 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to
 166	 * have the same Revision ID and Subsystem ID, but we assume they
 167	 * do.
 168	 */
 169	pci_read_config_dword(virtfn, PCI_CLASS_REVISION,
 170			      &physfn->sriov->class);
 171	pci_read_config_byte(virtfn, PCI_HEADER_TYPE,
 172			     &physfn->sriov->hdr_type);
 173	pci_read_config_word(virtfn, PCI_SUBSYSTEM_VENDOR_ID,
 174			     &physfn->sriov->subsystem_vendor);
 175	pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID,
 176			     &physfn->sriov->subsystem_device);
 177}
 178
 179int pci_iov_sysfs_link(struct pci_dev *dev,
 180		struct pci_dev *virtfn, int id)
 181{
 182	char buf[VIRTFN_ID_LEN];
 183	int rc;
 184
 185	sprintf(buf, "virtfn%u", id);
 186	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
 187	if (rc)
 188		goto failed;
 189	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
 190	if (rc)
 191		goto failed1;
 192
 193	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
 194
 195	return 0;
 196
 197failed1:
 198	sysfs_remove_link(&dev->dev.kobj, buf);
 199failed:
 200	return rc;
 201}
 202
 203#ifdef CONFIG_PCI_MSI
 204static ssize_t sriov_vf_total_msix_show(struct device *dev,
 205					struct device_attribute *attr,
 206					char *buf)
 207{
 208	struct pci_dev *pdev = to_pci_dev(dev);
 209	u32 vf_total_msix = 0;
 210
 211	device_lock(dev);
 212	if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix)
 213		goto unlock;
 214
 215	vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev);
 216unlock:
 217	device_unlock(dev);
 218	return sysfs_emit(buf, "%u\n", vf_total_msix);
 219}
 220static DEVICE_ATTR_RO(sriov_vf_total_msix);
 221
 222static ssize_t sriov_vf_msix_count_store(struct device *dev,
 223					 struct device_attribute *attr,
 224					 const char *buf, size_t count)
 225{
 226	struct pci_dev *vf_dev = to_pci_dev(dev);
 227	struct pci_dev *pdev = pci_physfn(vf_dev);
 228	int val, ret = 0;
 229
 230	if (kstrtoint(buf, 0, &val) < 0)
 231		return -EINVAL;
 
 232
 233	if (val < 0)
 234		return -EINVAL;
 235
 236	device_lock(&pdev->dev);
 237	if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) {
 238		ret = -EOPNOTSUPP;
 239		goto err_pdev;
 240	}
 241
 242	device_lock(&vf_dev->dev);
 243	if (vf_dev->driver) {
 244		/*
 245		 * A driver is already attached to this VF and has configured
 246		 * itself based on the current MSI-X vector count. Changing
 247		 * the vector size could mess up the driver, so block it.
 248		 */
 249		ret = -EBUSY;
 250		goto err_dev;
 251	}
 252
 253	ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val);
 254
 255err_dev:
 256	device_unlock(&vf_dev->dev);
 257err_pdev:
 258	device_unlock(&pdev->dev);
 259	return ret ? : count;
 260}
 261static DEVICE_ATTR_WO(sriov_vf_msix_count);
 262#endif
 263
 264static struct attribute *sriov_vf_dev_attrs[] = {
 265#ifdef CONFIG_PCI_MSI
 266	&dev_attr_sriov_vf_msix_count.attr,
 267#endif
 268	NULL,
 269};
 270
 271static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj,
 272					  struct attribute *a, int n)
 273{
 274	struct device *dev = kobj_to_dev(kobj);
 275	struct pci_dev *pdev = to_pci_dev(dev);
 276
 277	if (!pdev->is_virtfn)
 278		return 0;
 279
 280	return a->mode;
 281}
 282
 283const struct attribute_group sriov_vf_dev_attr_group = {
 284	.attrs = sriov_vf_dev_attrs,
 285	.is_visible = sriov_vf_attrs_are_visible,
 286};
 287
 288int pci_iov_add_virtfn(struct pci_dev *dev, int id)
 289{
 290	int i;
 291	int rc = -ENOMEM;
 292	u64 size;
 293	struct pci_dev *virtfn;
 294	struct resource *res;
 295	struct pci_sriov *iov = dev->sriov;
 296	struct pci_bus *bus;
 297
 298	bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id));
 299	if (!bus)
 300		goto failed;
 301
 302	virtfn = pci_alloc_dev(bus);
 303	if (!virtfn)
 304		goto failed0;
 305
 306	virtfn->devfn = pci_iov_virtfn_devfn(dev, id);
 307	virtfn->vendor = dev->vendor;
 308	virtfn->device = iov->vf_device;
 309	virtfn->is_virtfn = 1;
 310	virtfn->physfn = pci_dev_get(dev);
 311	virtfn->no_command_memory = 1;
 312
 313	if (id == 0)
 314		pci_read_vf_config_common(virtfn);
 315
 316	rc = pci_setup_device(virtfn);
 317	if (rc)
 318		goto failed1;
 319
 320	virtfn->dev.parent = dev->dev.parent;
 321	virtfn->multifunction = 0;
 322
 323	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 324		res = &dev->resource[i + PCI_IOV_RESOURCES];
 325		if (!res->parent)
 326			continue;
 327		virtfn->resource[i].name = pci_name(virtfn);
 328		virtfn->resource[i].flags = res->flags;
 329		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
 330		resource_set_range(&virtfn->resource[i],
 331				   res->start + size * id, size);
 332		rc = request_resource(res, &virtfn->resource[i]);
 333		BUG_ON(rc);
 334	}
 335
 336	pci_device_add(virtfn, virtfn->bus);
 337	rc = pci_iov_sysfs_link(dev, virtfn, id);
 338	if (rc)
 339		goto failed1;
 340
 341	pci_bus_add_device(virtfn);
 342
 343	return 0;
 344
 345failed1:
 346	pci_stop_and_remove_bus_device(virtfn);
 347	pci_dev_put(dev);
 348failed0:
 349	virtfn_remove_bus(dev->bus, bus);
 350failed:
 351
 352	return rc;
 353}
 354
 355void pci_iov_remove_virtfn(struct pci_dev *dev, int id)
 356{
 357	char buf[VIRTFN_ID_LEN];
 358	struct pci_dev *virtfn;
 359
 360	virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
 361					     pci_iov_virtfn_bus(dev, id),
 362					     pci_iov_virtfn_devfn(dev, id));
 363	if (!virtfn)
 364		return;
 365
 366	sprintf(buf, "virtfn%u", id);
 367	sysfs_remove_link(&dev->dev.kobj, buf);
 368	/*
 369	 * pci_stop_dev() could have been called for this virtfn already,
 370	 * so the directory for the virtfn may have been removed before.
 371	 * Double check to avoid spurious sysfs warnings.
 372	 */
 373	if (virtfn->dev.kobj.sd)
 374		sysfs_remove_link(&virtfn->dev.kobj, "physfn");
 375
 376	pci_stop_and_remove_bus_device(virtfn);
 377	virtfn_remove_bus(dev->bus, virtfn->bus);
 378
 379	/* balance pci_get_domain_bus_and_slot() */
 380	pci_dev_put(virtfn);
 381	pci_dev_put(dev);
 382}
 383
 384static ssize_t sriov_totalvfs_show(struct device *dev,
 385				   struct device_attribute *attr,
 386				   char *buf)
 387{
 388	struct pci_dev *pdev = to_pci_dev(dev);
 389
 390	return sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
 391}
 392
 393static ssize_t sriov_numvfs_show(struct device *dev,
 394				 struct device_attribute *attr,
 395				 char *buf)
 396{
 397	struct pci_dev *pdev = to_pci_dev(dev);
 398	u16 num_vfs;
 399
 400	/* Serialize vs sriov_numvfs_store() so readers see valid num_VFs */
 401	device_lock(&pdev->dev);
 402	num_vfs = pdev->sriov->num_VFs;
 403	device_unlock(&pdev->dev);
 404
 405	return sysfs_emit(buf, "%u\n", num_vfs);
 406}
 407
 408/*
 409 * num_vfs > 0; number of VFs to enable
 410 * num_vfs = 0; disable all VFs
 411 *
 412 * Note: SRIOV spec does not allow partial VF
 413 *	 disable, so it's all or none.
 414 */
 415static ssize_t sriov_numvfs_store(struct device *dev,
 416				  struct device_attribute *attr,
 417				  const char *buf, size_t count)
 418{
 419	struct pci_dev *pdev = to_pci_dev(dev);
 420	int ret = 0;
 421	u16 num_vfs;
 422
 423	if (kstrtou16(buf, 0, &num_vfs) < 0)
 424		return -EINVAL;
 
 425
 426	if (num_vfs > pci_sriov_get_totalvfs(pdev))
 427		return -ERANGE;
 428
 429	device_lock(&pdev->dev);
 430
 431	if (num_vfs == pdev->sriov->num_VFs)
 432		goto exit;
 433
 434	/* is PF driver loaded */
 435	if (!pdev->driver) {
 436		pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
 437		ret = -ENOENT;
 438		goto exit;
 439	}
 440
 441	/* is PF driver loaded w/callback */
 442	if (!pdev->driver->sriov_configure) {
 443		pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
 444		ret = -ENOENT;
 445		goto exit;
 446	}
 447
 448	if (num_vfs == 0) {
 449		/* disable VFs */
 450		ret = pdev->driver->sriov_configure(pdev, 0);
 451		goto exit;
 452	}
 453
 454	/* enable VFs */
 455	if (pdev->sriov->num_VFs) {
 456		pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
 457			 pdev->sriov->num_VFs, num_vfs);
 458		ret = -EBUSY;
 459		goto exit;
 460	}
 461
 462	ret = pdev->driver->sriov_configure(pdev, num_vfs);
 463	if (ret < 0)
 464		goto exit;
 465
 466	if (ret != num_vfs)
 467		pci_warn(pdev, "%d VFs requested; only %d enabled\n",
 468			 num_vfs, ret);
 469
 470exit:
 471	device_unlock(&pdev->dev);
 472
 473	if (ret < 0)
 474		return ret;
 475
 476	return count;
 477}
 478
 479static ssize_t sriov_offset_show(struct device *dev,
 480				 struct device_attribute *attr,
 481				 char *buf)
 482{
 483	struct pci_dev *pdev = to_pci_dev(dev);
 484
 485	return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
 486}
 487
 488static ssize_t sriov_stride_show(struct device *dev,
 489				 struct device_attribute *attr,
 490				 char *buf)
 491{
 492	struct pci_dev *pdev = to_pci_dev(dev);
 493
 494	return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
 495}
 496
 497static ssize_t sriov_vf_device_show(struct device *dev,
 498				    struct device_attribute *attr,
 499				    char *buf)
 500{
 501	struct pci_dev *pdev = to_pci_dev(dev);
 502
 503	return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
 504}
 505
 506static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
 507					    struct device_attribute *attr,
 508					    char *buf)
 509{
 510	struct pci_dev *pdev = to_pci_dev(dev);
 511
 512	return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
 513}
 514
 515static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
 516					     struct device_attribute *attr,
 517					     const char *buf, size_t count)
 518{
 519	struct pci_dev *pdev = to_pci_dev(dev);
 520	bool drivers_autoprobe;
 521
 522	if (kstrtobool(buf, &drivers_autoprobe) < 0)
 523		return -EINVAL;
 524
 525	pdev->sriov->drivers_autoprobe = drivers_autoprobe;
 526
 527	return count;
 528}
 529
 530static DEVICE_ATTR_RO(sriov_totalvfs);
 531static DEVICE_ATTR_RW(sriov_numvfs);
 532static DEVICE_ATTR_RO(sriov_offset);
 533static DEVICE_ATTR_RO(sriov_stride);
 534static DEVICE_ATTR_RO(sriov_vf_device);
 535static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
 536
 537static struct attribute *sriov_pf_dev_attrs[] = {
 538	&dev_attr_sriov_totalvfs.attr,
 539	&dev_attr_sriov_numvfs.attr,
 540	&dev_attr_sriov_offset.attr,
 541	&dev_attr_sriov_stride.attr,
 542	&dev_attr_sriov_vf_device.attr,
 543	&dev_attr_sriov_drivers_autoprobe.attr,
 544#ifdef CONFIG_PCI_MSI
 545	&dev_attr_sriov_vf_total_msix.attr,
 546#endif
 547	NULL,
 548};
 549
 550static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
 551					  struct attribute *a, int n)
 552{
 553	struct device *dev = kobj_to_dev(kobj);
 554
 555	if (!dev_is_pf(dev))
 556		return 0;
 557
 558	return a->mode;
 559}
 560
 561const struct attribute_group sriov_pf_dev_attr_group = {
 562	.attrs = sriov_pf_dev_attrs,
 563	.is_visible = sriov_pf_attrs_are_visible,
 564};
 565
 566int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
 567{
 568	return 0;
 569}
 570
 571int __weak pcibios_sriov_disable(struct pci_dev *pdev)
 572{
 573	return 0;
 574}
 575
 576static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
 577{
 578	unsigned int i;
 579	int rc;
 580
 581	if (dev->no_vf_scan)
 582		return 0;
 583
 584	for (i = 0; i < num_vfs; i++) {
 585		rc = pci_iov_add_virtfn(dev, i);
 586		if (rc)
 587			goto failed;
 588	}
 589	return 0;
 590failed:
 591	while (i--)
 592		pci_iov_remove_virtfn(dev, i);
 593
 594	return rc;
 595}
 596
 597static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
 598{
 599	int rc;
 600	int i;
 601	int nres;
 602	u16 initial;
 603	struct resource *res;
 604	struct pci_dev *pdev;
 605	struct pci_sriov *iov = dev->sriov;
 606	int bars = 0;
 607	int bus;
 608
 609	if (!nr_virtfn)
 610		return 0;
 611
 612	if (iov->num_VFs)
 613		return -EINVAL;
 614
 615	pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
 616	if (initial > iov->total_VFs ||
 617	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
 618		return -EIO;
 619
 620	if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
 621	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
 622		return -EINVAL;
 623
 624	nres = 0;
 625	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 626		bars |= (1 << (i + PCI_IOV_RESOURCES));
 627		res = &dev->resource[i + PCI_IOV_RESOURCES];
 628		if (res->parent)
 629			nres++;
 630	}
 631	if (nres != iov->nres) {
 632		pci_err(dev, "not enough MMIO resources for SR-IOV\n");
 633		return -ENOMEM;
 634	}
 635
 636	bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
 637	if (bus > dev->bus->busn_res.end) {
 638		pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
 639			nr_virtfn, bus, &dev->bus->busn_res);
 640		return -ENOMEM;
 641	}
 642
 643	if (pci_enable_resources(dev, bars)) {
 644		pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
 645		return -ENOMEM;
 646	}
 647
 648	if (iov->link != dev->devfn) {
 649		pdev = pci_get_slot(dev->bus, iov->link);
 650		if (!pdev)
 651			return -ENODEV;
 652
 653		if (!pdev->is_physfn) {
 654			pci_dev_put(pdev);
 655			return -ENOSYS;
 656		}
 657
 658		rc = sysfs_create_link(&dev->dev.kobj,
 659					&pdev->dev.kobj, "dep_link");
 660		pci_dev_put(pdev);
 661		if (rc)
 662			return rc;
 663	}
 664
 665	iov->initial_VFs = initial;
 666	if (nr_virtfn < initial)
 667		initial = nr_virtfn;
 668
 669	rc = pcibios_sriov_enable(dev, initial);
 670	if (rc) {
 671		pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
 672		goto err_pcibios;
 673	}
 674
 675	pci_iov_set_numvfs(dev, nr_virtfn);
 676	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
 677	pci_cfg_access_lock(dev);
 678	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 679	msleep(100);
 680	pci_cfg_access_unlock(dev);
 681
 682	rc = sriov_add_vfs(dev, initial);
 683	if (rc)
 684		goto err_pcibios;
 685
 686	kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
 687	iov->num_VFs = nr_virtfn;
 688
 689	return 0;
 690
 691err_pcibios:
 692	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
 693	pci_cfg_access_lock(dev);
 694	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 695	ssleep(1);
 696	pci_cfg_access_unlock(dev);
 697
 698	pcibios_sriov_disable(dev);
 699
 700	if (iov->link != dev->devfn)
 701		sysfs_remove_link(&dev->dev.kobj, "dep_link");
 702
 703	pci_iov_set_numvfs(dev, 0);
 704	return rc;
 705}
 706
 707static void sriov_del_vfs(struct pci_dev *dev)
 708{
 709	struct pci_sriov *iov = dev->sriov;
 710	int i;
 711
 712	for (i = 0; i < iov->num_VFs; i++)
 713		pci_iov_remove_virtfn(dev, i);
 714}
 715
 716static void sriov_disable(struct pci_dev *dev)
 717{
 718	struct pci_sriov *iov = dev->sriov;
 719
 720	if (!iov->num_VFs)
 721		return;
 722
 723	sriov_del_vfs(dev);
 724	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
 725	pci_cfg_access_lock(dev);
 726	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 727	ssleep(1);
 728	pci_cfg_access_unlock(dev);
 729
 730	pcibios_sriov_disable(dev);
 731
 732	if (iov->link != dev->devfn)
 733		sysfs_remove_link(&dev->dev.kobj, "dep_link");
 734
 735	iov->num_VFs = 0;
 736	pci_iov_set_numvfs(dev, 0);
 737}
 738
 739static int sriov_init(struct pci_dev *dev, int pos)
 740{
 741	int i, bar64;
 742	int rc;
 743	int nres;
 744	u32 pgsz;
 745	u16 ctrl, total;
 746	struct pci_sriov *iov;
 747	struct resource *res;
 748	const char *res_name;
 749	struct pci_dev *pdev;
 750
 751	pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
 752	if (ctrl & PCI_SRIOV_CTRL_VFE) {
 753		pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
 754		ssleep(1);
 755	}
 756
 757	ctrl = 0;
 758	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
 759		if (pdev->is_physfn)
 760			goto found;
 761
 762	pdev = NULL;
 763	if (pci_ari_enabled(dev->bus))
 764		ctrl |= PCI_SRIOV_CTRL_ARI;
 765
 766found:
 767	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
 768
 769	pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
 770	if (!total)
 771		return 0;
 772
 773	pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
 774	i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
 775	pgsz &= ~((1 << i) - 1);
 776	if (!pgsz)
 777		return -EIO;
 778
 779	pgsz &= ~(pgsz - 1);
 780	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
 781
 782	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
 783	if (!iov)
 784		return -ENOMEM;
 785
 786	nres = 0;
 787	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 788		res = &dev->resource[i + PCI_IOV_RESOURCES];
 789		res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
 790
 791		/*
 792		 * If it is already FIXED, don't change it, something
 793		 * (perhaps EA or header fixups) wants it this way.
 794		 */
 795		if (res->flags & IORESOURCE_PCI_FIXED)
 796			bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
 797		else
 798			bar64 = __pci_read_base(dev, pci_bar_unknown, res,
 799						pos + PCI_SRIOV_BAR + i * 4);
 800		if (!res->flags)
 801			continue;
 802		if (resource_size(res) & (PAGE_SIZE - 1)) {
 803			rc = -EIO;
 804			goto failed;
 805		}
 806		iov->barsz[i] = resource_size(res);
 807		resource_set_size(res, resource_size(res) * total);
 808		pci_info(dev, "%s %pR: contains BAR %d for %d VFs\n",
 809			 res_name, res, i, total);
 810		i += bar64;
 811		nres++;
 812	}
 813
 814	iov->pos = pos;
 815	iov->nres = nres;
 816	iov->ctrl = ctrl;
 817	iov->total_VFs = total;
 818	iov->driver_max_VFs = total;
 819	pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
 820	iov->pgsz = pgsz;
 821	iov->self = dev;
 822	iov->drivers_autoprobe = true;
 823	pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
 824	pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
 825	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
 826		iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
 827
 828	if (pdev)
 829		iov->dev = pci_dev_get(pdev);
 830	else
 831		iov->dev = dev;
 832
 833	dev->sriov = iov;
 834	dev->is_physfn = 1;
 835	rc = compute_max_vf_buses(dev);
 836	if (rc)
 837		goto fail_max_buses;
 838
 839	return 0;
 840
 841fail_max_buses:
 842	dev->sriov = NULL;
 843	dev->is_physfn = 0;
 844failed:
 845	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 846		res = &dev->resource[i + PCI_IOV_RESOURCES];
 847		res->flags = 0;
 848	}
 849
 850	kfree(iov);
 851	return rc;
 852}
 853
 854static void sriov_release(struct pci_dev *dev)
 855{
 856	BUG_ON(dev->sriov->num_VFs);
 857
 858	if (dev != dev->sriov->dev)
 859		pci_dev_put(dev->sriov->dev);
 860
 861	kfree(dev->sriov);
 862	dev->sriov = NULL;
 863}
 864
 865static void sriov_restore_state(struct pci_dev *dev)
 866{
 867	int i;
 868	u16 ctrl;
 869	struct pci_sriov *iov = dev->sriov;
 870
 871	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
 872	if (ctrl & PCI_SRIOV_CTRL_VFE)
 873		return;
 874
 875	/*
 876	 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
 877	 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
 878	 */
 879	ctrl &= ~PCI_SRIOV_CTRL_ARI;
 880	ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
 881	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
 882
 883	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
 884		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
 885
 886	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
 887	pci_iov_set_numvfs(dev, iov->num_VFs);
 888	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 889	if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
 890		msleep(100);
 891}
 892
 893/**
 894 * pci_iov_init - initialize the IOV capability
 895 * @dev: the PCI device
 896 *
 897 * Returns 0 on success, or negative on failure.
 898 */
 899int pci_iov_init(struct pci_dev *dev)
 900{
 901	int pos;
 902
 903	if (!pci_is_pcie(dev))
 904		return -ENODEV;
 905
 906	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
 907	if (pos)
 908		return sriov_init(dev, pos);
 909
 910	return -ENODEV;
 911}
 912
 913/**
 914 * pci_iov_release - release resources used by the IOV capability
 915 * @dev: the PCI device
 916 */
 917void pci_iov_release(struct pci_dev *dev)
 918{
 919	if (dev->is_physfn)
 920		sriov_release(dev);
 921}
 922
 923/**
 924 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
 925 * @dev: the PCI device
 926 */
 927void pci_iov_remove(struct pci_dev *dev)
 928{
 929	struct pci_sriov *iov = dev->sriov;
 930
 931	if (!dev->is_physfn)
 932		return;
 933
 934	iov->driver_max_VFs = iov->total_VFs;
 935	if (iov->num_VFs)
 936		pci_warn(dev, "driver left SR-IOV enabled after remove\n");
 937}
 938
 939/**
 940 * pci_iov_update_resource - update a VF BAR
 941 * @dev: the PCI device
 942 * @resno: the resource number
 943 *
 944 * Update a VF BAR in the SR-IOV capability of a PF.
 945 */
 946void pci_iov_update_resource(struct pci_dev *dev, int resno)
 947{
 948	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
 949	struct resource *res = dev->resource + resno;
 950	int vf_bar = resno - PCI_IOV_RESOURCES;
 951	struct pci_bus_region region;
 952	u16 cmd;
 953	u32 new;
 954	int reg;
 955
 956	/*
 957	 * The generic pci_restore_bars() path calls this for all devices,
 958	 * including VFs and non-SR-IOV devices.  If this is not a PF, we
 959	 * have nothing to do.
 960	 */
 961	if (!iov)
 962		return;
 963
 964	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
 965	if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
 966		dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
 967			 vf_bar, res);
 968		return;
 969	}
 970
 971	/*
 972	 * Ignore unimplemented BARs, unused resource slots for 64-bit
 973	 * BARs, and non-movable resources, e.g., those described via
 974	 * Enhanced Allocation.
 975	 */
 976	if (!res->flags)
 977		return;
 978
 979	if (res->flags & IORESOURCE_UNSET)
 980		return;
 981
 982	if (res->flags & IORESOURCE_PCI_FIXED)
 983		return;
 984
 985	pcibios_resource_to_bus(dev->bus, &region, res);
 986	new = region.start;
 987	new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
 988
 989	reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
 990	pci_write_config_dword(dev, reg, new);
 991	if (res->flags & IORESOURCE_MEM_64) {
 992		new = region.start >> 16 >> 16;
 993		pci_write_config_dword(dev, reg + 4, new);
 994	}
 995}
 996
 997resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
 998						      int resno)
 999{
1000	return pci_iov_resource_size(dev, resno);
1001}
1002
1003/**
1004 * pci_sriov_resource_alignment - get resource alignment for VF BAR
1005 * @dev: the PCI device
1006 * @resno: the resource number
1007 *
1008 * Returns the alignment of the VF BAR found in the SR-IOV capability.
1009 * This is not the same as the resource size which is defined as
1010 * the VF BAR size multiplied by the number of VFs.  The alignment
1011 * is just the VF BAR size.
1012 */
1013resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
1014{
1015	return pcibios_iov_resource_alignment(dev, resno);
1016}
1017
1018/**
1019 * pci_restore_iov_state - restore the state of the IOV capability
1020 * @dev: the PCI device
1021 */
1022void pci_restore_iov_state(struct pci_dev *dev)
1023{
1024	if (dev->is_physfn)
1025		sriov_restore_state(dev);
1026}
1027
1028/**
1029 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
1030 * @dev: the PCI device
1031 * @auto_probe: set VF drivers auto probe flag
1032 */
1033void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
1034{
1035	if (dev->is_physfn)
1036		dev->sriov->drivers_autoprobe = auto_probe;
1037}
1038
1039/**
1040 * pci_iov_bus_range - find bus range used by Virtual Function
1041 * @bus: the PCI bus
1042 *
1043 * Returns max number of buses (exclude current one) used by Virtual
1044 * Functions.
1045 */
1046int pci_iov_bus_range(struct pci_bus *bus)
1047{
1048	int max = 0;
1049	struct pci_dev *dev;
1050
1051	list_for_each_entry(dev, &bus->devices, bus_list) {
1052		if (!dev->is_physfn)
1053			continue;
1054		if (dev->sriov->max_VF_buses > max)
1055			max = dev->sriov->max_VF_buses;
1056	}
1057
1058	return max ? max - bus->number : 0;
1059}
1060
1061/**
1062 * pci_enable_sriov - enable the SR-IOV capability
1063 * @dev: the PCI device
1064 * @nr_virtfn: number of virtual functions to enable
1065 *
1066 * Returns 0 on success, or negative on failure.
1067 */
1068int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
1069{
1070	might_sleep();
1071
1072	if (!dev->is_physfn)
1073		return -ENOSYS;
1074
1075	return sriov_enable(dev, nr_virtfn);
1076}
1077EXPORT_SYMBOL_GPL(pci_enable_sriov);
1078
1079/**
1080 * pci_disable_sriov - disable the SR-IOV capability
1081 * @dev: the PCI device
1082 */
1083void pci_disable_sriov(struct pci_dev *dev)
1084{
1085	might_sleep();
1086
1087	if (!dev->is_physfn)
1088		return;
1089
1090	sriov_disable(dev);
1091}
1092EXPORT_SYMBOL_GPL(pci_disable_sriov);
1093
1094/**
1095 * pci_num_vf - return number of VFs associated with a PF device_release_driver
1096 * @dev: the PCI device
1097 *
1098 * Returns number of VFs, or 0 if SR-IOV is not enabled.
1099 */
1100int pci_num_vf(struct pci_dev *dev)
1101{
1102	if (!dev->is_physfn)
1103		return 0;
1104
1105	return dev->sriov->num_VFs;
1106}
1107EXPORT_SYMBOL_GPL(pci_num_vf);
1108
1109/**
1110 * pci_vfs_assigned - returns number of VFs are assigned to a guest
1111 * @dev: the PCI device
1112 *
1113 * Returns number of VFs belonging to this device that are assigned to a guest.
1114 * If device is not a physical function returns 0.
1115 */
1116int pci_vfs_assigned(struct pci_dev *dev)
1117{
1118	struct pci_dev *vfdev;
1119	unsigned int vfs_assigned = 0;
1120	unsigned short dev_id;
1121
1122	/* only search if we are a PF */
1123	if (!dev->is_physfn)
1124		return 0;
1125
1126	/*
1127	 * determine the device ID for the VFs, the vendor ID will be the
1128	 * same as the PF so there is no need to check for that one
1129	 */
1130	dev_id = dev->sriov->vf_device;
1131
1132	/* loop through all the VFs to see if we own any that are assigned */
1133	vfdev = pci_get_device(dev->vendor, dev_id, NULL);
1134	while (vfdev) {
1135		/*
1136		 * It is considered assigned if it is a virtual function with
1137		 * our dev as the physical function and the assigned bit is set
1138		 */
1139		if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
1140			pci_is_dev_assigned(vfdev))
1141			vfs_assigned++;
1142
1143		vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1144	}
1145
1146	return vfs_assigned;
1147}
1148EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1149
1150/**
1151 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1152 * @dev: the PCI PF device
1153 * @numvfs: number that should be used for TotalVFs supported
1154 *
1155 * Should be called from PF driver's probe routine with
1156 * device's mutex held.
1157 *
1158 * Returns 0 if PF is an SRIOV-capable device and
1159 * value of numvfs valid. If not a PF return -ENOSYS;
1160 * if numvfs is invalid return -EINVAL;
1161 * if VFs already enabled, return -EBUSY.
1162 */
1163int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1164{
1165	if (!dev->is_physfn)
1166		return -ENOSYS;
1167
1168	if (numvfs > dev->sriov->total_VFs)
1169		return -EINVAL;
1170
1171	/* Shouldn't change if VFs already enabled */
1172	if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1173		return -EBUSY;
1174
1175	dev->sriov->driver_max_VFs = numvfs;
1176	return 0;
1177}
1178EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1179
1180/**
1181 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1182 * @dev: the PCI PF device
1183 *
1184 * For a PCIe device with SRIOV support, return the PCIe
1185 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1186 * if the driver reduced it.  Otherwise 0.
1187 */
1188int pci_sriov_get_totalvfs(struct pci_dev *dev)
1189{
1190	if (!dev->is_physfn)
1191		return 0;
1192
1193	return dev->sriov->driver_max_VFs;
1194}
1195EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1196
1197/**
1198 * pci_sriov_configure_simple - helper to configure SR-IOV
1199 * @dev: the PCI device
1200 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1201 *
1202 * Enable or disable SR-IOV for devices that don't require any PF setup
1203 * before enabling SR-IOV.  Return value is negative on error, or number of
1204 * VFs allocated on success.
1205 */
1206int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1207{
1208	int rc;
1209
1210	might_sleep();
1211
1212	if (!dev->is_physfn)
1213		return -ENODEV;
1214
1215	if (pci_vfs_assigned(dev)) {
1216		pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1217		return -EPERM;
1218	}
1219
1220	if (nr_virtfn == 0) {
1221		sriov_disable(dev);
1222		return 0;
1223	}
1224
1225	rc = sriov_enable(dev, nr_virtfn);
1226	if (rc < 0)
1227		return rc;
1228
1229	return nr_virtfn;
1230}
1231EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);
v5.14.15
   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
  19int 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
  27int 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}
  34EXPORT_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 */
  42static 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 */
  58static 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
  75out:
  76	pci_iov_set_numvfs(dev, 0);
  77	return rc;
  78}
  79
  80static 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
 100static 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
 106resource_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
 114static 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
 137int 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
 155failed1:
 156	sysfs_remove_link(&dev->dev.kobj, buf);
 157failed:
 158	return rc;
 159}
 160
 161#ifdef CONFIG_PCI_MSI
 162static 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);
 174unlock:
 175	device_unlock(dev);
 176	return sysfs_emit(buf, "%u\n", vf_total_msix);
 177}
 178static DEVICE_ATTR_RO(sriov_vf_total_msix);
 179
 180static 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
 214err_dev:
 215	device_unlock(&vf_dev->dev);
 216err_pdev:
 217	device_unlock(&pdev->dev);
 218	return ret ? : count;
 219}
 220static DEVICE_ATTR_WO(sriov_vf_msix_count);
 221#endif
 222
 223static 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
 230static 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
 242const struct attribute_group sriov_vf_dev_attr_group = {
 243	.attrs = sriov_vf_dev_attrs,
 244	.is_visible = sriov_vf_attrs_are_visible,
 245};
 246
 247int 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
 304failed1:
 305	pci_stop_and_remove_bus_device(virtfn);
 306	pci_dev_put(dev);
 307failed0:
 308	virtfn_remove_bus(dev->bus, bus);
 309failed:
 310
 311	return rc;
 312}
 313
 314void 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
 343static 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 sysfs_emit(buf, "%u\n", pci_sriov_get_totalvfs(pdev));
 350}
 351
 352static 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 sysfs_emit(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 */
 374static 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 */
 395	if (!pdev->driver) {
 396		pci_info(pdev, "no driver bound to device; cannot configure SR-IOV\n");
 397		ret = -ENOENT;
 398		goto exit;
 399	}
 400
 401	/* is PF driver loaded w/callback */
 402	if (!pdev->driver->sriov_configure) {
 403		pci_info(pdev, "driver does not support SR-IOV configuration via sysfs\n");
 404		ret = -ENOENT;
 405		goto exit;
 406	}
 407
 408	if (num_vfs == 0) {
 409		/* disable VFs */
 410		ret = pdev->driver->sriov_configure(pdev, 0);
 411		goto exit;
 412	}
 413
 414	/* enable VFs */
 415	if (pdev->sriov->num_VFs) {
 416		pci_warn(pdev, "%d VFs already enabled. Disable before enabling %d VFs\n",
 417			 pdev->sriov->num_VFs, num_vfs);
 418		ret = -EBUSY;
 419		goto exit;
 420	}
 421
 422	ret = pdev->driver->sriov_configure(pdev, num_vfs);
 423	if (ret < 0)
 424		goto exit;
 425
 426	if (ret != num_vfs)
 427		pci_warn(pdev, "%d VFs requested; only %d enabled\n",
 428			 num_vfs, ret);
 429
 430exit:
 431	device_unlock(&pdev->dev);
 432
 433	if (ret < 0)
 434		return ret;
 435
 436	return count;
 437}
 438
 439static ssize_t sriov_offset_show(struct device *dev,
 440				 struct device_attribute *attr,
 441				 char *buf)
 442{
 443	struct pci_dev *pdev = to_pci_dev(dev);
 444
 445	return sysfs_emit(buf, "%u\n", pdev->sriov->offset);
 446}
 447
 448static ssize_t sriov_stride_show(struct device *dev,
 449				 struct device_attribute *attr,
 450				 char *buf)
 451{
 452	struct pci_dev *pdev = to_pci_dev(dev);
 453
 454	return sysfs_emit(buf, "%u\n", pdev->sriov->stride);
 455}
 456
 457static ssize_t sriov_vf_device_show(struct device *dev,
 458				    struct device_attribute *attr,
 459				    char *buf)
 460{
 461	struct pci_dev *pdev = to_pci_dev(dev);
 462
 463	return sysfs_emit(buf, "%x\n", pdev->sriov->vf_device);
 464}
 465
 466static ssize_t sriov_drivers_autoprobe_show(struct device *dev,
 467					    struct device_attribute *attr,
 468					    char *buf)
 469{
 470	struct pci_dev *pdev = to_pci_dev(dev);
 471
 472	return sysfs_emit(buf, "%u\n", pdev->sriov->drivers_autoprobe);
 473}
 474
 475static ssize_t sriov_drivers_autoprobe_store(struct device *dev,
 476					     struct device_attribute *attr,
 477					     const char *buf, size_t count)
 478{
 479	struct pci_dev *pdev = to_pci_dev(dev);
 480	bool drivers_autoprobe;
 481
 482	if (kstrtobool(buf, &drivers_autoprobe) < 0)
 483		return -EINVAL;
 484
 485	pdev->sriov->drivers_autoprobe = drivers_autoprobe;
 486
 487	return count;
 488}
 489
 490static DEVICE_ATTR_RO(sriov_totalvfs);
 491static DEVICE_ATTR_RW(sriov_numvfs);
 492static DEVICE_ATTR_RO(sriov_offset);
 493static DEVICE_ATTR_RO(sriov_stride);
 494static DEVICE_ATTR_RO(sriov_vf_device);
 495static DEVICE_ATTR_RW(sriov_drivers_autoprobe);
 496
 497static struct attribute *sriov_pf_dev_attrs[] = {
 498	&dev_attr_sriov_totalvfs.attr,
 499	&dev_attr_sriov_numvfs.attr,
 500	&dev_attr_sriov_offset.attr,
 501	&dev_attr_sriov_stride.attr,
 502	&dev_attr_sriov_vf_device.attr,
 503	&dev_attr_sriov_drivers_autoprobe.attr,
 504#ifdef CONFIG_PCI_MSI
 505	&dev_attr_sriov_vf_total_msix.attr,
 506#endif
 507	NULL,
 508};
 509
 510static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj,
 511					  struct attribute *a, int n)
 512{
 513	struct device *dev = kobj_to_dev(kobj);
 514
 515	if (!dev_is_pf(dev))
 516		return 0;
 517
 518	return a->mode;
 519}
 520
 521const struct attribute_group sriov_pf_dev_attr_group = {
 522	.attrs = sriov_pf_dev_attrs,
 523	.is_visible = sriov_pf_attrs_are_visible,
 524};
 525
 526int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
 527{
 528	return 0;
 529}
 530
 531int __weak pcibios_sriov_disable(struct pci_dev *pdev)
 532{
 533	return 0;
 534}
 535
 536static int sriov_add_vfs(struct pci_dev *dev, u16 num_vfs)
 537{
 538	unsigned int i;
 539	int rc;
 540
 541	if (dev->no_vf_scan)
 542		return 0;
 543
 544	for (i = 0; i < num_vfs; i++) {
 545		rc = pci_iov_add_virtfn(dev, i);
 546		if (rc)
 547			goto failed;
 548	}
 549	return 0;
 550failed:
 551	while (i--)
 552		pci_iov_remove_virtfn(dev, i);
 553
 554	return rc;
 555}
 556
 557static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
 558{
 559	int rc;
 560	int i;
 561	int nres;
 562	u16 initial;
 563	struct resource *res;
 564	struct pci_dev *pdev;
 565	struct pci_sriov *iov = dev->sriov;
 566	int bars = 0;
 567	int bus;
 568
 569	if (!nr_virtfn)
 570		return 0;
 571
 572	if (iov->num_VFs)
 573		return -EINVAL;
 574
 575	pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
 576	if (initial > iov->total_VFs ||
 577	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total_VFs)))
 578		return -EIO;
 579
 580	if (nr_virtfn < 0 || nr_virtfn > iov->total_VFs ||
 581	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
 582		return -EINVAL;
 583
 584	nres = 0;
 585	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 586		bars |= (1 << (i + PCI_IOV_RESOURCES));
 587		res = &dev->resource[i + PCI_IOV_RESOURCES];
 588		if (res->parent)
 589			nres++;
 590	}
 591	if (nres != iov->nres) {
 592		pci_err(dev, "not enough MMIO resources for SR-IOV\n");
 593		return -ENOMEM;
 594	}
 595
 596	bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
 597	if (bus > dev->bus->busn_res.end) {
 598		pci_err(dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
 599			nr_virtfn, bus, &dev->bus->busn_res);
 600		return -ENOMEM;
 601	}
 602
 603	if (pci_enable_resources(dev, bars)) {
 604		pci_err(dev, "SR-IOV: IOV BARS not allocated\n");
 605		return -ENOMEM;
 606	}
 607
 608	if (iov->link != dev->devfn) {
 609		pdev = pci_get_slot(dev->bus, iov->link);
 610		if (!pdev)
 611			return -ENODEV;
 612
 613		if (!pdev->is_physfn) {
 614			pci_dev_put(pdev);
 615			return -ENOSYS;
 616		}
 617
 618		rc = sysfs_create_link(&dev->dev.kobj,
 619					&pdev->dev.kobj, "dep_link");
 620		pci_dev_put(pdev);
 621		if (rc)
 622			return rc;
 623	}
 624
 625	iov->initial_VFs = initial;
 626	if (nr_virtfn < initial)
 627		initial = nr_virtfn;
 628
 629	rc = pcibios_sriov_enable(dev, initial);
 630	if (rc) {
 631		pci_err(dev, "failure %d from pcibios_sriov_enable()\n", rc);
 632		goto err_pcibios;
 633	}
 634
 635	pci_iov_set_numvfs(dev, nr_virtfn);
 636	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
 637	pci_cfg_access_lock(dev);
 638	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 639	msleep(100);
 640	pci_cfg_access_unlock(dev);
 641
 642	rc = sriov_add_vfs(dev, initial);
 643	if (rc)
 644		goto err_pcibios;
 645
 646	kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
 647	iov->num_VFs = nr_virtfn;
 648
 649	return 0;
 650
 651err_pcibios:
 652	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
 653	pci_cfg_access_lock(dev);
 654	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 655	ssleep(1);
 656	pci_cfg_access_unlock(dev);
 657
 658	pcibios_sriov_disable(dev);
 659
 660	if (iov->link != dev->devfn)
 661		sysfs_remove_link(&dev->dev.kobj, "dep_link");
 662
 663	pci_iov_set_numvfs(dev, 0);
 664	return rc;
 665}
 666
 667static void sriov_del_vfs(struct pci_dev *dev)
 668{
 669	struct pci_sriov *iov = dev->sriov;
 670	int i;
 671
 672	for (i = 0; i < iov->num_VFs; i++)
 673		pci_iov_remove_virtfn(dev, i);
 674}
 675
 676static void sriov_disable(struct pci_dev *dev)
 677{
 678	struct pci_sriov *iov = dev->sriov;
 679
 680	if (!iov->num_VFs)
 681		return;
 682
 683	sriov_del_vfs(dev);
 684	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
 685	pci_cfg_access_lock(dev);
 686	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 687	ssleep(1);
 688	pci_cfg_access_unlock(dev);
 689
 690	pcibios_sriov_disable(dev);
 691
 692	if (iov->link != dev->devfn)
 693		sysfs_remove_link(&dev->dev.kobj, "dep_link");
 694
 695	iov->num_VFs = 0;
 696	pci_iov_set_numvfs(dev, 0);
 697}
 698
 699static int sriov_init(struct pci_dev *dev, int pos)
 700{
 701	int i, bar64;
 702	int rc;
 703	int nres;
 704	u32 pgsz;
 705	u16 ctrl, total;
 706	struct pci_sriov *iov;
 707	struct resource *res;
 
 708	struct pci_dev *pdev;
 709
 710	pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
 711	if (ctrl & PCI_SRIOV_CTRL_VFE) {
 712		pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
 713		ssleep(1);
 714	}
 715
 716	ctrl = 0;
 717	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
 718		if (pdev->is_physfn)
 719			goto found;
 720
 721	pdev = NULL;
 722	if (pci_ari_enabled(dev->bus))
 723		ctrl |= PCI_SRIOV_CTRL_ARI;
 724
 725found:
 726	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
 727
 728	pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
 729	if (!total)
 730		return 0;
 731
 732	pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
 733	i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
 734	pgsz &= ~((1 << i) - 1);
 735	if (!pgsz)
 736		return -EIO;
 737
 738	pgsz &= ~(pgsz - 1);
 739	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
 740
 741	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
 742	if (!iov)
 743		return -ENOMEM;
 744
 745	nres = 0;
 746	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 747		res = &dev->resource[i + PCI_IOV_RESOURCES];
 
 
 748		/*
 749		 * If it is already FIXED, don't change it, something
 750		 * (perhaps EA or header fixups) wants it this way.
 751		 */
 752		if (res->flags & IORESOURCE_PCI_FIXED)
 753			bar64 = (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
 754		else
 755			bar64 = __pci_read_base(dev, pci_bar_unknown, res,
 756						pos + PCI_SRIOV_BAR + i * 4);
 757		if (!res->flags)
 758			continue;
 759		if (resource_size(res) & (PAGE_SIZE - 1)) {
 760			rc = -EIO;
 761			goto failed;
 762		}
 763		iov->barsz[i] = resource_size(res);
 764		res->end = res->start + resource_size(res) * total - 1;
 765		pci_info(dev, "VF(n) BAR%d space: %pR (contains BAR%d for %d VFs)\n",
 766			 i, res, i, total);
 767		i += bar64;
 768		nres++;
 769	}
 770
 771	iov->pos = pos;
 772	iov->nres = nres;
 773	iov->ctrl = ctrl;
 774	iov->total_VFs = total;
 775	iov->driver_max_VFs = total;
 776	pci_read_config_word(dev, pos + PCI_SRIOV_VF_DID, &iov->vf_device);
 777	iov->pgsz = pgsz;
 778	iov->self = dev;
 779	iov->drivers_autoprobe = true;
 780	pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
 781	pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
 782	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
 783		iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
 784
 785	if (pdev)
 786		iov->dev = pci_dev_get(pdev);
 787	else
 788		iov->dev = dev;
 789
 790	dev->sriov = iov;
 791	dev->is_physfn = 1;
 792	rc = compute_max_vf_buses(dev);
 793	if (rc)
 794		goto fail_max_buses;
 795
 796	return 0;
 797
 798fail_max_buses:
 799	dev->sriov = NULL;
 800	dev->is_physfn = 0;
 801failed:
 802	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
 803		res = &dev->resource[i + PCI_IOV_RESOURCES];
 804		res->flags = 0;
 805	}
 806
 807	kfree(iov);
 808	return rc;
 809}
 810
 811static void sriov_release(struct pci_dev *dev)
 812{
 813	BUG_ON(dev->sriov->num_VFs);
 814
 815	if (dev != dev->sriov->dev)
 816		pci_dev_put(dev->sriov->dev);
 817
 818	kfree(dev->sriov);
 819	dev->sriov = NULL;
 820}
 821
 822static void sriov_restore_state(struct pci_dev *dev)
 823{
 824	int i;
 825	u16 ctrl;
 826	struct pci_sriov *iov = dev->sriov;
 827
 828	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
 829	if (ctrl & PCI_SRIOV_CTRL_VFE)
 830		return;
 831
 832	/*
 833	 * Restore PCI_SRIOV_CTRL_ARI before pci_iov_set_numvfs() because
 834	 * it reads offset & stride, which depend on PCI_SRIOV_CTRL_ARI.
 835	 */
 836	ctrl &= ~PCI_SRIOV_CTRL_ARI;
 837	ctrl |= iov->ctrl & PCI_SRIOV_CTRL_ARI;
 838	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
 839
 840	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
 841		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
 842
 843	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
 844	pci_iov_set_numvfs(dev, iov->num_VFs);
 845	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
 846	if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
 847		msleep(100);
 848}
 849
 850/**
 851 * pci_iov_init - initialize the IOV capability
 852 * @dev: the PCI device
 853 *
 854 * Returns 0 on success, or negative on failure.
 855 */
 856int pci_iov_init(struct pci_dev *dev)
 857{
 858	int pos;
 859
 860	if (!pci_is_pcie(dev))
 861		return -ENODEV;
 862
 863	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
 864	if (pos)
 865		return sriov_init(dev, pos);
 866
 867	return -ENODEV;
 868}
 869
 870/**
 871 * pci_iov_release - release resources used by the IOV capability
 872 * @dev: the PCI device
 873 */
 874void pci_iov_release(struct pci_dev *dev)
 875{
 876	if (dev->is_physfn)
 877		sriov_release(dev);
 878}
 879
 880/**
 881 * pci_iov_remove - clean up SR-IOV state after PF driver is detached
 882 * @dev: the PCI device
 883 */
 884void pci_iov_remove(struct pci_dev *dev)
 885{
 886	struct pci_sriov *iov = dev->sriov;
 887
 888	if (!dev->is_physfn)
 889		return;
 890
 891	iov->driver_max_VFs = iov->total_VFs;
 892	if (iov->num_VFs)
 893		pci_warn(dev, "driver left SR-IOV enabled after remove\n");
 894}
 895
 896/**
 897 * pci_iov_update_resource - update a VF BAR
 898 * @dev: the PCI device
 899 * @resno: the resource number
 900 *
 901 * Update a VF BAR in the SR-IOV capability of a PF.
 902 */
 903void pci_iov_update_resource(struct pci_dev *dev, int resno)
 904{
 905	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
 906	struct resource *res = dev->resource + resno;
 907	int vf_bar = resno - PCI_IOV_RESOURCES;
 908	struct pci_bus_region region;
 909	u16 cmd;
 910	u32 new;
 911	int reg;
 912
 913	/*
 914	 * The generic pci_restore_bars() path calls this for all devices,
 915	 * including VFs and non-SR-IOV devices.  If this is not a PF, we
 916	 * have nothing to do.
 917	 */
 918	if (!iov)
 919		return;
 920
 921	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &cmd);
 922	if ((cmd & PCI_SRIOV_CTRL_VFE) && (cmd & PCI_SRIOV_CTRL_MSE)) {
 923		dev_WARN(&dev->dev, "can't update enabled VF BAR%d %pR\n",
 924			 vf_bar, res);
 925		return;
 926	}
 927
 928	/*
 929	 * Ignore unimplemented BARs, unused resource slots for 64-bit
 930	 * BARs, and non-movable resources, e.g., those described via
 931	 * Enhanced Allocation.
 932	 */
 933	if (!res->flags)
 934		return;
 935
 936	if (res->flags & IORESOURCE_UNSET)
 937		return;
 938
 939	if (res->flags & IORESOURCE_PCI_FIXED)
 940		return;
 941
 942	pcibios_resource_to_bus(dev->bus, &region, res);
 943	new = region.start;
 944	new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
 945
 946	reg = iov->pos + PCI_SRIOV_BAR + 4 * vf_bar;
 947	pci_write_config_dword(dev, reg, new);
 948	if (res->flags & IORESOURCE_MEM_64) {
 949		new = region.start >> 16 >> 16;
 950		pci_write_config_dword(dev, reg + 4, new);
 951	}
 952}
 953
 954resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
 955						      int resno)
 956{
 957	return pci_iov_resource_size(dev, resno);
 958}
 959
 960/**
 961 * pci_sriov_resource_alignment - get resource alignment for VF BAR
 962 * @dev: the PCI device
 963 * @resno: the resource number
 964 *
 965 * Returns the alignment of the VF BAR found in the SR-IOV capability.
 966 * This is not the same as the resource size which is defined as
 967 * the VF BAR size multiplied by the number of VFs.  The alignment
 968 * is just the VF BAR size.
 969 */
 970resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
 971{
 972	return pcibios_iov_resource_alignment(dev, resno);
 973}
 974
 975/**
 976 * pci_restore_iov_state - restore the state of the IOV capability
 977 * @dev: the PCI device
 978 */
 979void pci_restore_iov_state(struct pci_dev *dev)
 980{
 981	if (dev->is_physfn)
 982		sriov_restore_state(dev);
 983}
 984
 985/**
 986 * pci_vf_drivers_autoprobe - set PF property drivers_autoprobe for VFs
 987 * @dev: the PCI device
 988 * @auto_probe: set VF drivers auto probe flag
 989 */
 990void pci_vf_drivers_autoprobe(struct pci_dev *dev, bool auto_probe)
 991{
 992	if (dev->is_physfn)
 993		dev->sriov->drivers_autoprobe = auto_probe;
 994}
 995
 996/**
 997 * pci_iov_bus_range - find bus range used by Virtual Function
 998 * @bus: the PCI bus
 999 *
1000 * Returns max number of buses (exclude current one) used by Virtual
1001 * Functions.
1002 */
1003int pci_iov_bus_range(struct pci_bus *bus)
1004{
1005	int max = 0;
1006	struct pci_dev *dev;
1007
1008	list_for_each_entry(dev, &bus->devices, bus_list) {
1009		if (!dev->is_physfn)
1010			continue;
1011		if (dev->sriov->max_VF_buses > max)
1012			max = dev->sriov->max_VF_buses;
1013	}
1014
1015	return max ? max - bus->number : 0;
1016}
1017
1018/**
1019 * pci_enable_sriov - enable the SR-IOV capability
1020 * @dev: the PCI device
1021 * @nr_virtfn: number of virtual functions to enable
1022 *
1023 * Returns 0 on success, or negative on failure.
1024 */
1025int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
1026{
1027	might_sleep();
1028
1029	if (!dev->is_physfn)
1030		return -ENOSYS;
1031
1032	return sriov_enable(dev, nr_virtfn);
1033}
1034EXPORT_SYMBOL_GPL(pci_enable_sriov);
1035
1036/**
1037 * pci_disable_sriov - disable the SR-IOV capability
1038 * @dev: the PCI device
1039 */
1040void pci_disable_sriov(struct pci_dev *dev)
1041{
1042	might_sleep();
1043
1044	if (!dev->is_physfn)
1045		return;
1046
1047	sriov_disable(dev);
1048}
1049EXPORT_SYMBOL_GPL(pci_disable_sriov);
1050
1051/**
1052 * pci_num_vf - return number of VFs associated with a PF device_release_driver
1053 * @dev: the PCI device
1054 *
1055 * Returns number of VFs, or 0 if SR-IOV is not enabled.
1056 */
1057int pci_num_vf(struct pci_dev *dev)
1058{
1059	if (!dev->is_physfn)
1060		return 0;
1061
1062	return dev->sriov->num_VFs;
1063}
1064EXPORT_SYMBOL_GPL(pci_num_vf);
1065
1066/**
1067 * pci_vfs_assigned - returns number of VFs are assigned to a guest
1068 * @dev: the PCI device
1069 *
1070 * Returns number of VFs belonging to this device that are assigned to a guest.
1071 * If device is not a physical function returns 0.
1072 */
1073int pci_vfs_assigned(struct pci_dev *dev)
1074{
1075	struct pci_dev *vfdev;
1076	unsigned int vfs_assigned = 0;
1077	unsigned short dev_id;
1078
1079	/* only search if we are a PF */
1080	if (!dev->is_physfn)
1081		return 0;
1082
1083	/*
1084	 * determine the device ID for the VFs, the vendor ID will be the
1085	 * same as the PF so there is no need to check for that one
1086	 */
1087	dev_id = dev->sriov->vf_device;
1088
1089	/* loop through all the VFs to see if we own any that are assigned */
1090	vfdev = pci_get_device(dev->vendor, dev_id, NULL);
1091	while (vfdev) {
1092		/*
1093		 * It is considered assigned if it is a virtual function with
1094		 * our dev as the physical function and the assigned bit is set
1095		 */
1096		if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
1097			pci_is_dev_assigned(vfdev))
1098			vfs_assigned++;
1099
1100		vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
1101	}
1102
1103	return vfs_assigned;
1104}
1105EXPORT_SYMBOL_GPL(pci_vfs_assigned);
1106
1107/**
1108 * pci_sriov_set_totalvfs -- reduce the TotalVFs available
1109 * @dev: the PCI PF device
1110 * @numvfs: number that should be used for TotalVFs supported
1111 *
1112 * Should be called from PF driver's probe routine with
1113 * device's mutex held.
1114 *
1115 * Returns 0 if PF is an SRIOV-capable device and
1116 * value of numvfs valid. If not a PF return -ENOSYS;
1117 * if numvfs is invalid return -EINVAL;
1118 * if VFs already enabled, return -EBUSY.
1119 */
1120int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
1121{
1122	if (!dev->is_physfn)
1123		return -ENOSYS;
1124
1125	if (numvfs > dev->sriov->total_VFs)
1126		return -EINVAL;
1127
1128	/* Shouldn't change if VFs already enabled */
1129	if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
1130		return -EBUSY;
1131
1132	dev->sriov->driver_max_VFs = numvfs;
1133	return 0;
1134}
1135EXPORT_SYMBOL_GPL(pci_sriov_set_totalvfs);
1136
1137/**
1138 * pci_sriov_get_totalvfs -- get total VFs supported on this device
1139 * @dev: the PCI PF device
1140 *
1141 * For a PCIe device with SRIOV support, return the PCIe
1142 * SRIOV capability value of TotalVFs or the value of driver_max_VFs
1143 * if the driver reduced it.  Otherwise 0.
1144 */
1145int pci_sriov_get_totalvfs(struct pci_dev *dev)
1146{
1147	if (!dev->is_physfn)
1148		return 0;
1149
1150	return dev->sriov->driver_max_VFs;
1151}
1152EXPORT_SYMBOL_GPL(pci_sriov_get_totalvfs);
1153
1154/**
1155 * pci_sriov_configure_simple - helper to configure SR-IOV
1156 * @dev: the PCI device
1157 * @nr_virtfn: number of virtual functions to enable, 0 to disable
1158 *
1159 * Enable or disable SR-IOV for devices that don't require any PF setup
1160 * before enabling SR-IOV.  Return value is negative on error, or number of
1161 * VFs allocated on success.
1162 */
1163int pci_sriov_configure_simple(struct pci_dev *dev, int nr_virtfn)
1164{
1165	int rc;
1166
1167	might_sleep();
1168
1169	if (!dev->is_physfn)
1170		return -ENODEV;
1171
1172	if (pci_vfs_assigned(dev)) {
1173		pci_warn(dev, "Cannot modify SR-IOV while VFs are assigned\n");
1174		return -EPERM;
1175	}
1176
1177	if (nr_virtfn == 0) {
1178		sriov_disable(dev);
1179		return 0;
1180	}
1181
1182	rc = sriov_enable(dev, nr_virtfn);
1183	if (rc < 0)
1184		return rc;
1185
1186	return nr_virtfn;
1187}
1188EXPORT_SYMBOL_GPL(pci_sriov_configure_simple);