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1// SPDX-License-Identifier: GPL-2.02/*3 * PCI Express I/O Virtualization (IOV) support4 *   Single Root IOV 1.05 *   Address Translation Service 1.06 *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 PF51 * @dev: VF pci_dev52 * @pf_driver: Device driver required to own the PF53 *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 until59 * pci_enable_sriov() is called and pci_disable_sriov() does not return until60 * all VF drivers have completed their remove().61 *62 * The PF driver must call pci_disable_sriov() before it begins to destroy the63 * 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 may80 * 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 Stride95 * determine how many additional bus numbers will be consumed by VFs.96 *97 * Iterate over all valid NumVFs, validate offset and stride, and calculate98 * 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 the163	 * other VFs.164	 *165	 * PCIe r4.0, sec 9.3.4.1, technically doesn't require all VFs to166	 * have the same Revision ID and Subsystem ID, but we assume they167	 * 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_MSI204static 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 configured246		 * itself based on the current MSI-X vector count. Changing247		 * 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#endif263 264static struct attribute *sriov_vf_dev_attrs[] = {265#ifdef CONFIG_PCI_MSI266	&dev_attr_sriov_vf_msix_count.attr,267#endif268	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		virtfn->resource[i].start = res->start + size * id;331		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;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 enable410 * num_vfs = 0; disable all VFs411 *412 * Note: SRIOV spec does not allow partial VF413 *	 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_MSI545	&dev_attr_sriov_vf_total_msix.attr,546#endif547	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, something793		 * (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		else798			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		res->end = res->start + resource_size(res) * total - 1;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	else831		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() because877	 * 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 capability895 * @dev: the PCI device896 *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 capability915 * @dev: the PCI device916 */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 detached925 * @dev: the PCI device926 */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 BAR941 * @dev: the PCI device942 * @resno: the resource number943 *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, we959	 * 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-bit973	 * BARs, and non-movable resources, e.g., those described via974	 * 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 BAR1005 * @dev: the PCI device1006 * @resno: the resource number1007 *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 as1010 * the VF BAR size multiplied by the number of VFs.  The alignment1011 * 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 capability1020 * @dev: the PCI device1021 */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 VFs1030 * @dev: the PCI device1031 * @auto_probe: set VF drivers auto probe flag1032 */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 Function1041 * @bus: the PCI bus1042 *1043 * Returns max number of buses (exclude current one) used by Virtual1044 * 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 capability1063 * @dev: the PCI device1064 * @nr_virtfn: number of virtual functions to enable1065 *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 capability1081 * @dev: the PCI device1082 */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_driver1096 * @dev: the PCI device1097 *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 guest1111 * @dev: the PCI device1112 *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 the1128	 * same as the PF so there is no need to check for that one1129	 */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 with1137		 * our dev as the physical function and the assigned bit is set1138		 */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 available1152 * @dev: the PCI PF device1153 * @numvfs: number that should be used for TotalVFs supported1154 *1155 * Should be called from PF driver's probe routine with1156 * device's mutex held.1157 *1158 * Returns 0 if PF is an SRIOV-capable device and1159 * 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 device1182 * @dev: the PCI PF device1183 *1184 * For a PCIe device with SRIOV support, return the PCIe1185 * SRIOV capability value of TotalVFs or the value of driver_max_VFs1186 * 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-IOV1199 * @dev: the PCI device1200 * @nr_virtfn: number of virtual functions to enable, 0 to disable1201 *1202 * Enable or disable SR-IOV for devices that don't require any PF setup1203 * before enabling SR-IOV.  Return value is negative on error, or number of1204 * 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);1232