[deliverable/linux.git] / drivers / pci / iov.c

/*
 * drivers/pci/iov.c
 *
 * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
 *
 * PCI Express I/O Virtualization (IOV) support.
 *   Single Root IOV 1.0
 *   Address Translation Service 1.0
 */

#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/pci-ats.h>
#include "pci.h"

#define VIRTFN_ID_LEN	16

static inline u8 virtfn_bus(struct pci_dev *dev, int id)
{
	return dev->bus->number + ((dev->devfn + dev->sriov->offset +
				    dev->sriov->stride * id) >> 8);
}

static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
{
	return (dev->devfn + dev->sriov->offset +
		dev->sriov->stride * id) & 0xff;
}

static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr)
{
	int rc;
	struct pci_bus *child;

	if (bus->number == busnr)
		return bus;

	child = pci_find_bus(pci_domain_nr(bus), busnr);
	if (child)
		return child;

	child = pci_add_new_bus(bus, NULL, busnr);
	if (!child)
		return NULL;

	child->subordinate = busnr;
	child->dev.parent = bus->bridge;
	rc = pci_bus_add_child(child);
	if (rc) {
		pci_remove_bus(child);
		return NULL;
	}

	return child;
}

static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
{
	struct pci_bus *child;

	if (bus->number == busnr)
		return;

	child = pci_find_bus(pci_domain_nr(bus), busnr);
	BUG_ON(!child);

	if (list_empty(&child->devices))
		pci_remove_bus(child);
}

static int virtfn_add(struct pci_dev *dev, int id, int reset)
{
	int i;
	int rc;
	u64 size;
	char buf[VIRTFN_ID_LEN];
	struct pci_dev *virtfn;
	struct resource *res;
	struct pci_sriov *iov = dev->sriov;

	virtfn = alloc_pci_dev();
	if (!virtfn)
		return -ENOMEM;

	mutex_lock(&iov->dev->sriov->lock);
	virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
	if (!virtfn->bus) {
		kfree(virtfn);
		mutex_unlock(&iov->dev->sriov->lock);
		return -ENOMEM;
	}
	virtfn->devfn = virtfn_devfn(dev, id);
	virtfn->vendor = dev->vendor;
	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
	pci_setup_device(virtfn);
	virtfn->dev.parent = dev->dev.parent;

	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
		res = dev->resource + PCI_IOV_RESOURCES + i;
		if (!res->parent)
			continue;
		virtfn->resource[i].name = pci_name(virtfn);
		virtfn->resource[i].flags = res->flags;
		size = resource_size(res);
		do_div(size, iov->total);
		virtfn->resource[i].start = res->start + size * id;
		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
		rc = request_resource(res, &virtfn->resource[i]);
		BUG_ON(rc);
	}

	if (reset)
		__pci_reset_function(virtfn);

	pci_device_add(virtfn, virtfn->bus);
	mutex_unlock(&iov->dev->sriov->lock);

	virtfn->physfn = pci_dev_get(dev);
	virtfn->is_virtfn = 1;

	rc = pci_bus_add_device(virtfn);
	if (rc)
		goto failed1;
	sprintf(buf, "virtfn%u", id);
	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
	if (rc)
		goto failed1;
	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
	if (rc)
		goto failed2;

	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);

	return 0;

failed2:
	sysfs_remove_link(&dev->dev.kobj, buf);
failed1:
	pci_dev_put(dev);
	mutex_lock(&iov->dev->sriov->lock);
	pci_remove_bus_device(virtfn);
	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
	mutex_unlock(&iov->dev->sriov->lock);

	return rc;
}

static void virtfn_remove(struct pci_dev *dev, int id, int reset)
{
	char buf[VIRTFN_ID_LEN];
	struct pci_bus *bus;
	struct pci_dev *virtfn;
	struct pci_sriov *iov = dev->sriov;

	bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
	if (!bus)
		return;

	virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
	if (!virtfn)
		return;

	pci_dev_put(virtfn);

	if (reset) {
		device_release_driver(&virtfn->dev);
		__pci_reset_function(virtfn);
	}

	sprintf(buf, "virtfn%u", id);
	sysfs_remove_link(&dev->dev.kobj, buf);
	sysfs_remove_link(&virtfn->dev.kobj, "physfn");

	mutex_lock(&iov->dev->sriov->lock);
	pci_remove_bus_device(virtfn);
	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
	mutex_unlock(&iov->dev->sriov->lock);

	pci_dev_put(dev);
}

static int sriov_migration(struct pci_dev *dev)
{
	u16 status;
	struct pci_sriov *iov = dev->sriov;

	if (!iov->nr_virtfn)
		return 0;

	if (!(iov->cap & PCI_SRIOV_CAP_VFM))
		return 0;

	pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status);
	if (!(status & PCI_SRIOV_STATUS_VFM))
		return 0;

	schedule_work(&iov->mtask);

	return 1;
}

static void sriov_migration_task(struct work_struct *work)
{
	int i;
	u8 state;
	u16 status;
	struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask);

	for (i = iov->initial; i < iov->nr_virtfn; i++) {
		state = readb(iov->mstate + i);
		if (state == PCI_SRIOV_VFM_MI) {
			writeb(PCI_SRIOV_VFM_AV, iov->mstate + i);
			state = readb(iov->mstate + i);
			if (state == PCI_SRIOV_VFM_AV)
				virtfn_add(iov->self, i, 1);
		} else if (state == PCI_SRIOV_VFM_MO) {
			virtfn_remove(iov->self, i, 1);
			writeb(PCI_SRIOV_VFM_UA, iov->mstate + i);
			state = readb(iov->mstate + i);
			if (state == PCI_SRIOV_VFM_AV)
				virtfn_add(iov->self, i, 0);
		}
	}

	pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status);
	status &= ~PCI_SRIOV_STATUS_VFM;
	pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status);
}

static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn)
{
	int bir;
	u32 table;
	resource_size_t pa;
	struct pci_sriov *iov = dev->sriov;

	if (nr_virtfn <= iov->initial)
		return 0;

	pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table);
	bir = PCI_SRIOV_VFM_BIR(table);
	if (bir > PCI_STD_RESOURCE_END)
		return -EIO;

	table = PCI_SRIOV_VFM_OFFSET(table);
	if (table + nr_virtfn > pci_resource_len(dev, bir))
		return -EIO;

	pa = pci_resource_start(dev, bir) + table;
	iov->mstate = ioremap(pa, nr_virtfn);
	if (!iov->mstate)
		return -ENOMEM;

	INIT_WORK(&iov->mtask, sriov_migration_task);

	iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR;
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);

	return 0;
}

static void sriov_disable_migration(struct pci_dev *dev)
{
	struct pci_sriov *iov = dev->sriov;

	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);

	cancel_work_sync(&iov->mtask);
	iounmap(iov->mstate);
}

static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
{
	int rc;
	int i, j;
	int nres;
	u16 offset, stride, initial;
	struct resource *res;
	struct pci_dev *pdev;
	struct pci_sriov *iov = dev->sriov;

	if (!nr_virtfn)
		return 0;

	if (iov->nr_virtfn)
		return -EINVAL;

	pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
	if (initial > iov->total ||
	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total)))
		return -EIO;

	if (nr_virtfn < 0 || nr_virtfn > iov->total ||
	    (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
		return -EINVAL;

	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
	if (!offset || (nr_virtfn > 1 && !stride))
		return -EIO;

	nres = 0;
	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
		res = dev->resource + PCI_IOV_RESOURCES + i;
		if (res->parent)
			nres++;
	}
	if (nres != iov->nres) {
		dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
		return -ENOMEM;
	}

	iov->offset = offset;
	iov->stride = stride;

	if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) {
		dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
		return -ENOMEM;
	}

	if (iov->link != dev->devfn) {
		pdev = pci_get_slot(dev->bus, iov->link);
		if (!pdev)
			return -ENODEV;

		pci_dev_put(pdev);

		if (!pdev->is_physfn)
			return -ENODEV;

		rc = sysfs_create_link(&dev->dev.kobj,
					&pdev->dev.kobj, "dep_link");
		if (rc)
			return rc;
	}

	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
	pci_block_user_cfg_access(dev);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	msleep(100);
	pci_unblock_user_cfg_access(dev);

	iov->initial = initial;
	if (nr_virtfn < initial)
		initial = nr_virtfn;

	for (i = 0; i < initial; i++) {
		rc = virtfn_add(dev, i, 0);
		if (rc)
			goto failed;
	}

	if (iov->cap & PCI_SRIOV_CAP_VFM) {
		rc = sriov_enable_migration(dev, nr_virtfn);
		if (rc)
			goto failed;
	}

	kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
	iov->nr_virtfn = nr_virtfn;

	return 0;

failed:
	for (j = 0; j < i; j++)
		virtfn_remove(dev, j, 0);

	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
	pci_block_user_cfg_access(dev);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	ssleep(1);
	pci_unblock_user_cfg_access(dev);

	if (iov->link != dev->devfn)
		sysfs_remove_link(&dev->dev.kobj, "dep_link");

	return rc;
}

static void sriov_disable(struct pci_dev *dev)
{
	int i;
	struct pci_sriov *iov = dev->sriov;

	if (!iov->nr_virtfn)
		return;

	if (iov->cap & PCI_SRIOV_CAP_VFM)
		sriov_disable_migration(dev);

	for (i = 0; i < iov->nr_virtfn; i++)
		virtfn_remove(dev, i, 0);

	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE);
	pci_block_user_cfg_access(dev);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	ssleep(1);
	pci_unblock_user_cfg_access(dev);

	if (iov->link != dev->devfn)
		sysfs_remove_link(&dev->dev.kobj, "dep_link");

	iov->nr_virtfn = 0;
}

static int sriov_init(struct pci_dev *dev, int pos)
{
	int i;
	int rc;
	int nres;
	u32 pgsz;
	u16 ctrl, total, offset, stride;
	struct pci_sriov *iov;
	struct resource *res;
	struct pci_dev *pdev;

	if (dev->pcie_type != PCI_EXP_TYPE_RC_END &&
	    dev->pcie_type != PCI_EXP_TYPE_ENDPOINT)
		return -ENODEV;

	pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
	if (ctrl & PCI_SRIOV_CTRL_VFE) {
		pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
		ssleep(1);
	}

	pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
	if (!total)
		return 0;

	ctrl = 0;
	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
		if (pdev->is_physfn)
			goto found;

	pdev = NULL;
	if (pci_ari_enabled(dev->bus))
		ctrl |= PCI_SRIOV_CTRL_ARI;

found:
	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
	pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total);
	pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);
	pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);
	if (!offset || (total > 1 && !stride))
		return -EIO;

	pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
	i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
	pgsz &= ~((1 << i) - 1);
	if (!pgsz)
		return -EIO;

	pgsz &= ~(pgsz - 1);
	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);

	nres = 0;
	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
		res = dev->resource + PCI_IOV_RESOURCES + i;
		i += __pci_read_base(dev, pci_bar_unknown, res,
				     pos + PCI_SRIOV_BAR + i * 4);
		if (!res->flags)
			continue;
		if (resource_size(res) & (PAGE_SIZE - 1)) {
			rc = -EIO;
			goto failed;
		}
		res->end = res->start + resource_size(res) * total - 1;
		nres++;
	}

	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
	if (!iov) {
		rc = -ENOMEM;
		goto failed;
	}

	iov->pos = pos;
	iov->nres = nres;
	iov->ctrl = ctrl;
	iov->total = total;
	iov->offset = offset;
	iov->stride = stride;
	iov->pgsz = pgsz;
	iov->self = dev;
	pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
	pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
	if (dev->pcie_type == PCI_EXP_TYPE_RC_END)
		iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);

	if (pdev)
		iov->dev = pci_dev_get(pdev);
	else
		iov->dev = dev;

	mutex_init(&iov->lock);

	dev->sriov = iov;
	dev->is_physfn = 1;

	return 0;

failed:
	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
		res = dev->resource + PCI_IOV_RESOURCES + i;
		res->flags = 0;
	}

	return rc;
}

static void sriov_release(struct pci_dev *dev)
{
	BUG_ON(dev->sriov->nr_virtfn);

	if (dev != dev->sriov->dev)
		pci_dev_put(dev->sriov->dev);

	mutex_destroy(&dev->sriov->lock);

	kfree(dev->sriov);
	dev->sriov = NULL;
}

static void sriov_restore_state(struct pci_dev *dev)
{
	int i;
	u16 ctrl;
	struct pci_sriov *iov = dev->sriov;

	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
	if (ctrl & PCI_SRIOV_CTRL_VFE)
		return;

	for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
		pci_update_resource(dev, i);

	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn);
	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
		msleep(100);
}

/**
 * pci_iov_init - initialize the IOV capability
 * @dev: the PCI device
 *
 * Returns 0 on success, or negative on failure.
 */
int pci_iov_init(struct pci_dev *dev)
{
	int pos;

	if (!pci_is_pcie(dev))
		return -ENODEV;

	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
	if (pos)
		return sriov_init(dev, pos);

	return -ENODEV;
}

/**
 * pci_iov_release - release resources used by the IOV capability
 * @dev: the PCI device
 */
void pci_iov_release(struct pci_dev *dev)
{
	if (dev->is_physfn)
		sriov_release(dev);
}

/**
 * pci_iov_resource_bar - get position of the SR-IOV BAR
 * @dev: the PCI device
 * @resno: the resource number
 * @type: the BAR type to be filled in
 *
 * Returns position of the BAR encapsulated in the SR-IOV capability.
 */
int pci_iov_resource_bar(struct pci_dev *dev, int resno,
			 enum pci_bar_type *type)
{
	if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END)
		return 0;

	BUG_ON(!dev->is_physfn);

	*type = pci_bar_unknown;

	return dev->sriov->pos + PCI_SRIOV_BAR +
		4 * (resno - PCI_IOV_RESOURCES);
}

/**
 * pci_sriov_resource_alignment - get resource alignment for VF BAR
 * @dev: the PCI device
 * @resno: the resource number
 *
 * Returns the alignment of the VF BAR found in the SR-IOV capability.
 * This is not the same as the resource size which is defined as
 * the VF BAR size multiplied by the number of VFs.  The alignment
 * is just the VF BAR size.
 */
resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
{
	struct resource tmp;
	enum pci_bar_type type;
	int reg = pci_iov_resource_bar(dev, resno, &type);
	
	if (!reg)
		return 0;

	 __pci_read_base(dev, type, &tmp, reg);
	return resource_alignment(&tmp);
}

/**
 * pci_restore_iov_state - restore the state of the IOV capability
 * @dev: the PCI device
 */
void pci_restore_iov_state(struct pci_dev *dev)
{
	if (dev->is_physfn)
		sriov_restore_state(dev);
}

/**
 * pci_iov_bus_range - find bus range used by Virtual Function
 * @bus: the PCI bus
 *
 * Returns max number of buses (exclude current one) used by Virtual
 * Functions.
 */
int pci_iov_bus_range(struct pci_bus *bus)
{
	int max = 0;
	u8 busnr;
	struct pci_dev *dev;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		if (!dev->is_physfn)
			continue;
		busnr = virtfn_bus(dev, dev->sriov->total - 1);
		if (busnr > max)
			max = busnr;
	}

	return max ? max - bus->number : 0;
}

/**
 * pci_enable_sriov - enable the SR-IOV capability
 * @dev: the PCI device
 * @nr_virtfn: number of virtual functions to enable
 *
 * Returns 0 on success, or negative on failure.
 */
int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
{
	might_sleep();

	if (!dev->is_physfn)
		return -ENODEV;

	return sriov_enable(dev, nr_virtfn);
}
EXPORT_SYMBOL_GPL(pci_enable_sriov);

/**
 * pci_disable_sriov - disable the SR-IOV capability
 * @dev: the PCI device
 */
void pci_disable_sriov(struct pci_dev *dev)
{
	might_sleep();

	if (!dev->is_physfn)
		return;

	sriov_disable(dev);
}
EXPORT_SYMBOL_GPL(pci_disable_sriov);

/**
 * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration
 * @dev: the PCI device
 *
 * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not.
 *
 * Physical Function driver is responsible to register IRQ handler using
 * VF Migration Interrupt Message Number, and call this function when the
 * interrupt is generated by the hardware.
 */
irqreturn_t pci_sriov_migration(struct pci_dev *dev)
{
	if (!dev->is_physfn)
		return IRQ_NONE;

	return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE;
}
EXPORT_SYMBOL_GPL(pci_sriov_migration);

/**
 * pci_num_vf - return number of VFs associated with a PF device_release_driver
 * @dev: the PCI device
 *
 * Returns number of VFs, or 0 if SR-IOV is not enabled.
 */
int pci_num_vf(struct pci_dev *dev)
{
	if (!dev || !dev->is_physfn)
		return 0;
	else
		return dev->sriov->nr_virtfn;
}
EXPORT_SYMBOL_GPL(pci_num_vf);
Commit	Line	Data
d1b054da YZ	1	/*
	2	* drivers/pci/iov.c
	3	*
	4	* Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
	5	*
	6	* PCI Express I/O Virtualization (IOV) support.
	7	* Single Root IOV 1.0
302b4215	8	* Address Translation Service 1.0
d1b054da YZ	9	*/
	10
	11	#include <linux/pci.h>
5a0e3ad6	12	#include <linux/slab.h>
d1b054da	13	#include <linux/mutex.h>
363c75db	14	#include <linux/export.h>
d1b054da YZ	15	#include <linux/string.h>
d1b054da YZ	16	#include <linux/delay.h>
5cdede24	17	#include <linux/pci-ats.h>
d1b054da YZ	18	#include "pci.h"
d1b054da YZ	19
dd7cc44d	20	#define VIRTFN_ID_LEN 16
d1b054da	21
a28724b0 YZ	22	static inline u8 virtfn_bus(struct pci_dev *dev, int id)
	23	{
	24	return dev->bus->number + ((dev->devfn + dev->sriov->offset +
	25	dev->sriov->stride * id) >> 8);
	26	}
	27
	28	static inline u8 virtfn_devfn(struct pci_dev *dev, int id)
	29	{
	30	return (dev->devfn + dev->sriov->offset +
	31	dev->sriov->stride * id) & 0xff;
	32	}
	33
dd7cc44d YZ	34	static struct pci_bus virtfn_add_bus(struct pci_bus bus, int busnr)
	35	{
	36	int rc;
	37	struct pci_bus *child;
	38
	39	if (bus->number == busnr)
	40	return bus;
	41
	42	child = pci_find_bus(pci_domain_nr(bus), busnr);
	43	if (child)
	44	return child;
	45
	46	child = pci_add_new_bus(bus, NULL, busnr);
	47	if (!child)
	48	return NULL;
	49
	50	child->subordinate = busnr;
	51	child->dev.parent = bus->bridge;
	52	rc = pci_bus_add_child(child);
	53	if (rc) {
	54	pci_remove_bus(child);
	55	return NULL;
	56	}
	57
	58	return child;
	59	}
	60
	61	static void virtfn_remove_bus(struct pci_bus *bus, int busnr)
	62	{
	63	struct pci_bus *child;
	64
	65	if (bus->number == busnr)
	66	return;
	67
	68	child = pci_find_bus(pci_domain_nr(bus), busnr);
	69	BUG_ON(!child);
	70
	71	if (list_empty(&child->devices))
	72	pci_remove_bus(child);
	73	}
	74
	75	static int virtfn_add(struct pci_dev *dev, int id, int reset)
	76	{
	77	int i;
	78	int rc;
	79	u64 size;
	80	char buf[VIRTFN_ID_LEN];
	81	struct pci_dev *virtfn;
	82	struct resource *res;
	83	struct pci_sriov *iov = dev->sriov;
	84
	85	virtfn = alloc_pci_dev();
	86	if (!virtfn)
	87	return -ENOMEM;
	88
	89	mutex_lock(&iov->dev->sriov->lock);
	90	virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id));
	91	if (!virtfn->bus) {
	92	kfree(virtfn);
	93	mutex_unlock(&iov->dev->sriov->lock);
	94	return -ENOMEM;
	95	}
	96	virtfn->devfn = virtfn_devfn(dev, id);
	97	virtfn->vendor = dev->vendor;
98	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device);
99	pci_setup_device(virtfn);
100	virtfn->dev.parent = dev->dev.parent;
101
102	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
103	res = dev->resource + PCI_IOV_RESOURCES + i;
104	if (!res->parent)
105	continue;
106	virtfn->resource[i].name = pci_name(virtfn);
107	virtfn->resource[i].flags = res->flags;
108	size = resource_size(res);
109	do_div(size, iov->total);
110	virtfn->resource[i].start = res->start + size * id;
111	virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
112	rc = request_resource(res, &virtfn->resource[i]);
113	BUG_ON(rc);
114	}
115
116	if (reset)
8c1c699f	117	__pci_reset_function(virtfn);
dd7cc44d YZ	118
	119	pci_device_add(virtfn, virtfn->bus);
	120	mutex_unlock(&iov->dev->sriov->lock);
	121
	122	virtfn->physfn = pci_dev_get(dev);
	123	virtfn->is_virtfn = 1;
	124
	125	rc = pci_bus_add_device(virtfn);
	126	if (rc)
	127	goto failed1;
	128	sprintf(buf, "virtfn%u", id);
	129	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
	130	if (rc)
	131	goto failed1;
	132	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");
	133	if (rc)
	134	goto failed2;
	135
	136	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);
	137
	138	return 0;
	139
	140	failed2:
	141	sysfs_remove_link(&dev->dev.kobj, buf);
	142	failed1:
	143	pci_dev_put(dev);
	144	mutex_lock(&iov->dev->sriov->lock);
	145	pci_remove_bus_device(virtfn);
	146	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
	147	mutex_unlock(&iov->dev->sriov->lock);
	148
	149	return rc;
	150	}
	151
	152	static void virtfn_remove(struct pci_dev *dev, int id, int reset)
	153	{
	154	char buf[VIRTFN_ID_LEN];
	155	struct pci_bus *bus;
	156	struct pci_dev *virtfn;
	157	struct pci_sriov *iov = dev->sriov;
	158
	159	bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id));
	160	if (!bus)
	161	return;
	162
	163	virtfn = pci_get_slot(bus, virtfn_devfn(dev, id));
	164	if (!virtfn)
	165	return;
	166
	167	pci_dev_put(virtfn);
	168
	169	if (reset) {
	170	device_release_driver(&virtfn->dev);
8c1c699f	171	__pci_reset_function(virtfn);
dd7cc44d YZ	172	}
	173
	174	sprintf(buf, "virtfn%u", id);
	175	sysfs_remove_link(&dev->dev.kobj, buf);
	176	sysfs_remove_link(&virtfn->dev.kobj, "physfn");
	177
	178	mutex_lock(&iov->dev->sriov->lock);
	179	pci_remove_bus_device(virtfn);
	180	virtfn_remove_bus(dev->bus, virtfn_bus(dev, id));
	181	mutex_unlock(&iov->dev->sriov->lock);
	182
	183	pci_dev_put(dev);
	184	}
	185
74bb1bcc YZ	186	static int sriov_migration(struct pci_dev *dev)
	187	{
	188	u16 status;
	189	struct pci_sriov *iov = dev->sriov;
	190
	191	if (!iov->nr_virtfn)
	192	return 0;
	193
	194	if (!(iov->cap & PCI_SRIOV_CAP_VFM))
	195	return 0;
	196
	197	pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status);
	198	if (!(status & PCI_SRIOV_STATUS_VFM))
	199	return 0;
	200
	201	schedule_work(&iov->mtask);
	202
	203	return 1;
	204	}
	205
	206	static void sriov_migration_task(struct work_struct *work)
	207	{
	208	int i;
	209	u8 state;
	210	u16 status;
	211	struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask);
	212
	213	for (i = iov->initial; i < iov->nr_virtfn; i++) {
	214	state = readb(iov->mstate + i);
	215	if (state == PCI_SRIOV_VFM_MI) {
	216	writeb(PCI_SRIOV_VFM_AV, iov->mstate + i);
	217	state = readb(iov->mstate + i);
	218	if (state == PCI_SRIOV_VFM_AV)
	219	virtfn_add(iov->self, i, 1);
	220	} else if (state == PCI_SRIOV_VFM_MO) {
	221	virtfn_remove(iov->self, i, 1);
	222	writeb(PCI_SRIOV_VFM_UA, iov->mstate + i);
	223	state = readb(iov->mstate + i);
	224	if (state == PCI_SRIOV_VFM_AV)
	225	virtfn_add(iov->self, i, 0);
	226	}
	227	}
	228
	229	pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status);
	230	status &= ~PCI_SRIOV_STATUS_VFM;
	231	pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status);
	232	}
	233
	234	static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn)
	235	{
	236	int bir;
	237	u32 table;
	238	resource_size_t pa;
	239	struct pci_sriov *iov = dev->sriov;
	240
	241	if (nr_virtfn <= iov->initial)
	242	return 0;
	243
	244	pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table);
	245	bir = PCI_SRIOV_VFM_BIR(table);
	246	if (bir > PCI_STD_RESOURCE_END)
	247	return -EIO;
	248
	249	table = PCI_SRIOV_VFM_OFFSET(table);
250	if (table + nr_virtfn > pci_resource_len(dev, bir))
251	return -EIO;
252
253	pa = pci_resource_start(dev, bir) + table;
254	iov->mstate = ioremap(pa, nr_virtfn);
255	if (!iov->mstate)
256	return -ENOMEM;
257
258	INIT_WORK(&iov->mtask, sriov_migration_task);
259
260	iov->ctrl \|= PCI_SRIOV_CTRL_VFM \| PCI_SRIOV_CTRL_INTR;
261	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
262
263	return 0;
264	}
265
266	static void sriov_disable_migration(struct pci_dev *dev)
267	{
268	struct pci_sriov *iov = dev->sriov;
269
270	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM \| PCI_SRIOV_CTRL_INTR);
271	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
272
273	cancel_work_sync(&iov->mtask);
274	iounmap(iov->mstate);
275	}
276
dd7cc44d YZ	277	static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
	278	{
	279	int rc;
	280	int i, j;
	281	int nres;
	282	u16 offset, stride, initial;
	283	struct resource *res;
	284	struct pci_dev *pdev;
	285	struct pci_sriov *iov = dev->sriov;
	286
	287	if (!nr_virtfn)
	288	return 0;
	289
	290	if (iov->nr_virtfn)
	291	return -EINVAL;
	292
	293	pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial);
	294	if (initial > iov->total \|\|
	295	(!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total)))
	296	return -EIO;
	297
	298	if (nr_virtfn < 0 \|\| nr_virtfn > iov->total \|\|
	299	(!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
	300	return -EINVAL;
	301
	302	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
	303	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
	304	pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
	305	if (!offset \|\| (nr_virtfn > 1 && !stride))
	306	return -EIO;
	307
	308	nres = 0;
	309	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
	310	res = dev->resource + PCI_IOV_RESOURCES + i;
	311	if (res->parent)
	312	nres++;
	313	}
	314	if (nres != iov->nres) {
	315	dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n");
	316	return -ENOMEM;
	317	}
	318
	319	iov->offset = offset;
	320	iov->stride = stride;
	321
	322	if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) {
	323	dev_err(&dev->dev, "SR-IOV: bus number out of range\n");
	324	return -ENOMEM;
	325	}
	326
	327	if (iov->link != dev->devfn) {
	328	pdev = pci_get_slot(dev->bus, iov->link);
	329	if (!pdev)
	330	return -ENODEV;
	331
	332	pci_dev_put(pdev);
	333
	334	if (!pdev->is_physfn)
	335	return -ENODEV;
	336
	337	rc = sysfs_create_link(&dev->dev.kobj,
	338	&pdev->dev.kobj, "dep_link");
	339	if (rc)
	340	return rc;
341	}
342
343	iov->ctrl \|= PCI_SRIOV_CTRL_VFE \| PCI_SRIOV_CTRL_MSE;
344	pci_block_user_cfg_access(dev);
345	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
346	msleep(100);
347	pci_unblock_user_cfg_access(dev);
348
349	iov->initial = initial;
350	if (nr_virtfn < initial)
351	initial = nr_virtfn;
352
353	for (i = 0; i < initial; i++) {
354	rc = virtfn_add(dev, i, 0);
355	if (rc)
356	goto failed;
357	}
358
74bb1bcc YZ	359	if (iov->cap & PCI_SRIOV_CAP_VFM) {
	360	rc = sriov_enable_migration(dev, nr_virtfn);
	361	if (rc)
	362	goto failed;
	363	}
	364
dd7cc44d YZ	365	kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE);
	366	iov->nr_virtfn = nr_virtfn;
	367
	368	return 0;
	369
	370	failed:
	371	for (j = 0; j < i; j++)
	372	virtfn_remove(dev, j, 0);
	373
	374	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE \| PCI_SRIOV_CTRL_MSE);
	375	pci_block_user_cfg_access(dev);
	376	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	377	ssleep(1);
	378	pci_unblock_user_cfg_access(dev);
	379
	380	if (iov->link != dev->devfn)
	381	sysfs_remove_link(&dev->dev.kobj, "dep_link");
	382
	383	return rc;
	384	}
	385
	386	static void sriov_disable(struct pci_dev *dev)
	387	{
	388	int i;
	389	struct pci_sriov *iov = dev->sriov;
	390
	391	if (!iov->nr_virtfn)
	392	return;
	393
74bb1bcc YZ	394	if (iov->cap & PCI_SRIOV_CAP_VFM)
	395	sriov_disable_migration(dev);
	396
dd7cc44d YZ	397	for (i = 0; i < iov->nr_virtfn; i++)
	398	virtfn_remove(dev, i, 0);
	399
	400	iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE \| PCI_SRIOV_CTRL_MSE);
	401	pci_block_user_cfg_access(dev);
	402	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	403	ssleep(1);
	404	pci_unblock_user_cfg_access(dev);
	405
	406	if (iov->link != dev->devfn)
	407	sysfs_remove_link(&dev->dev.kobj, "dep_link");
	408
	409	iov->nr_virtfn = 0;
	410	}
	411
d1b054da YZ	412	static int sriov_init(struct pci_dev *dev, int pos)
	413	{
	414	int i;
	415	int rc;
	416	int nres;
	417	u32 pgsz;
	418	u16 ctrl, total, offset, stride;
	419	struct pci_sriov *iov;
	420	struct resource *res;
	421	struct pci_dev *pdev;
	422
	423	if (dev->pcie_type != PCI_EXP_TYPE_RC_END &&
	424	dev->pcie_type != PCI_EXP_TYPE_ENDPOINT)
	425	return -ENODEV;
	426
	427	pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl);
	428	if (ctrl & PCI_SRIOV_CTRL_VFE) {
	429	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0);
	430	ssleep(1);
	431	}
	432
	433	pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total);
	434	if (!total)
	435	return 0;
	436
	437	ctrl = 0;
	438	list_for_each_entry(pdev, &dev->bus->devices, bus_list)
	439	if (pdev->is_physfn)
	440	goto found;
	441
	442	pdev = NULL;
	443	if (pci_ari_enabled(dev->bus))
	444	ctrl \|= PCI_SRIOV_CTRL_ARI;
	445
	446	found:
	447	pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl);
	448	pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total);
	449	pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset);
	450	pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride);
	451	if (!offset \|\| (total > 1 && !stride))
	452	return -EIO;
	453
	454	pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz);
	455	i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0;
	456	pgsz &= ~((1 << i) - 1);
	457	if (!pgsz)
	458	return -EIO;
	459
	460	pgsz &= ~(pgsz - 1);
	461	pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz);
	462
	463	nres = 0;
	464	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
	465	res = dev->resource + PCI_IOV_RESOURCES + i;
	466	i += __pci_read_base(dev, pci_bar_unknown, res,
	467	pos + PCI_SRIOV_BAR + i * 4);
	468	if (!res->flags)
	469	continue;
	470	if (resource_size(res) & (PAGE_SIZE - 1)) {
	471	rc = -EIO;
	472	goto failed;
	473	}
	474	res->end = res->start + resource_size(res) * total - 1;
	475	nres++;
476	}
477
478	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
479	if (!iov) {
480	rc = -ENOMEM;
481	goto failed;
482	}
483
484	iov->pos = pos;
485	iov->nres = nres;
486	iov->ctrl = ctrl;
487	iov->total = total;
488	iov->offset = offset;
489	iov->stride = stride;
490	iov->pgsz = pgsz;
491	iov->self = dev;
492	pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap);
493	pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link);
4d135dbe YZ	494	if (dev->pcie_type == PCI_EXP_TYPE_RC_END)
4d135dbe YZ	495	iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), iov->link);
d1b054da YZ	496
	497	if (pdev)
	498	iov->dev = pci_dev_get(pdev);
e277d2fc	499	else
d1b054da	500	iov->dev = dev;
e277d2fc YZ	501
e277d2fc YZ	502	mutex_init(&iov->lock);
d1b054da YZ	503
	504	dev->sriov = iov;
	505	dev->is_physfn = 1;
	506
	507	return 0;
	508
	509	failed:
	510	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
	511	res = dev->resource + PCI_IOV_RESOURCES + i;
	512	res->flags = 0;
	513	}
	514
	515	return rc;
	516	}
	517
	518	static void sriov_release(struct pci_dev *dev)
	519	{
dd7cc44d YZ	520	BUG_ON(dev->sriov->nr_virtfn);
dd7cc44d YZ	521
e277d2fc	522	if (dev != dev->sriov->dev)
d1b054da YZ	523	pci_dev_put(dev->sriov->dev);
d1b054da YZ	524
e277d2fc YZ	525	mutex_destroy(&dev->sriov->lock);
e277d2fc YZ	526
d1b054da YZ	527	kfree(dev->sriov);
	528	dev->sriov = NULL;
	529	}
	530
8c5cdb6a YZ	531	static void sriov_restore_state(struct pci_dev *dev)
	532	{
	533	int i;
	534	u16 ctrl;
	535	struct pci_sriov *iov = dev->sriov;
	536
	537	pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl);
	538	if (ctrl & PCI_SRIOV_CTRL_VFE)
	539	return;
	540
	541	for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++)
	542	pci_update_resource(dev, i);
	543
	544	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
dd7cc44d	545	pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn);
8c5cdb6a YZ	546	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
	547	if (iov->ctrl & PCI_SRIOV_CTRL_VFE)
	548	msleep(100);
	549	}
	550
d1b054da YZ	551	/**
	552	* pci_iov_init - initialize the IOV capability
	553	* @dev: the PCI device
	554	*
	555	* Returns 0 on success, or negative on failure.
	556	*/
	557	int pci_iov_init(struct pci_dev *dev)
	558	{
	559	int pos;
	560
5f4d91a1	561	if (!pci_is_pcie(dev))
d1b054da YZ	562	return -ENODEV;
	563
	564	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV);
	565	if (pos)
	566	return sriov_init(dev, pos);
	567
	568	return -ENODEV;
	569	}
	570
	571	/**
	572	* pci_iov_release - release resources used by the IOV capability
	573	* @dev: the PCI device
	574	*/
	575	void pci_iov_release(struct pci_dev *dev)
	576	{
	577	if (dev->is_physfn)
	578	sriov_release(dev);
	579	}
	580
	581	/**
	582	* pci_iov_resource_bar - get position of the SR-IOV BAR
	583	* @dev: the PCI device
	584	* @resno: the resource number
	585	* @type: the BAR type to be filled in
	586	*
	587	* Returns position of the BAR encapsulated in the SR-IOV capability.
	588	*/
	589	int pci_iov_resource_bar(struct pci_dev *dev, int resno,
	590	enum pci_bar_type *type)
	591	{
	592	if (resno < PCI_IOV_RESOURCES \|\| resno > PCI_IOV_RESOURCE_END)
	593	return 0;
	594
	595	BUG_ON(!dev->is_physfn);
	596
	597	*type = pci_bar_unknown;
	598
	599	return dev->sriov->pos + PCI_SRIOV_BAR +
	600	4 * (resno - PCI_IOV_RESOURCES);
	601	}
8c5cdb6a	602
6faf17f6 CW	603	/**
	604	* pci_sriov_resource_alignment - get resource alignment for VF BAR
	605	* @dev: the PCI device
	606	* @resno: the resource number
	607	*
	608	* Returns the alignment of the VF BAR found in the SR-IOV capability.
	609	* This is not the same as the resource size which is defined as
	610	* the VF BAR size multiplied by the number of VFs. The alignment
	611	* is just the VF BAR size.
	612	*/
0e52247a	613	resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
6faf17f6 CW	614	{
	615	struct resource tmp;
	616	enum pci_bar_type type;
	617	int reg = pci_iov_resource_bar(dev, resno, &type);
	618
	619	if (!reg)
	620	return 0;
	621
	622	__pci_read_base(dev, type, &tmp, reg);
	623	return resource_alignment(&tmp);
	624	}
	625
8c5cdb6a YZ	626	/**
	627	* pci_restore_iov_state - restore the state of the IOV capability
	628	* @dev: the PCI device
	629	*/
	630	void pci_restore_iov_state(struct pci_dev *dev)
	631	{
	632	if (dev->is_physfn)
	633	sriov_restore_state(dev);
	634	}
a28724b0 YZ	635
	636	/**
	637	* pci_iov_bus_range - find bus range used by Virtual Function
	638	* @bus: the PCI bus
	639	*
	640	* Returns max number of buses (exclude current one) used by Virtual
	641	* Functions.
	642	*/
	643	int pci_iov_bus_range(struct pci_bus *bus)
	644	{
	645	int max = 0;
	646	u8 busnr;
	647	struct pci_dev *dev;
	648
	649	list_for_each_entry(dev, &bus->devices, bus_list) {
	650	if (!dev->is_physfn)
	651	continue;
	652	busnr = virtfn_bus(dev, dev->sriov->total - 1);
	653	if (busnr > max)
	654	max = busnr;
	655	}
	656
	657	return max ? max - bus->number : 0;
	658	}
dd7cc44d YZ	659
	660	/**
	661	* pci_enable_sriov - enable the SR-IOV capability
	662	* @dev: the PCI device
52a8873b	663	* @nr_virtfn: number of virtual functions to enable
dd7cc44d YZ	664	*
	665	* Returns 0 on success, or negative on failure.
	666	*/
	667	int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)
	668	{
	669	might_sleep();
	670
	671	if (!dev->is_physfn)
	672	return -ENODEV;
	673
	674	return sriov_enable(dev, nr_virtfn);
	675	}
	676	EXPORT_SYMBOL_GPL(pci_enable_sriov);
	677
	678	/**
	679	* pci_disable_sriov - disable the SR-IOV capability
	680	* @dev: the PCI device
	681	*/
	682	void pci_disable_sriov(struct pci_dev *dev)
	683	{
	684	might_sleep();
	685
	686	if (!dev->is_physfn)
	687	return;
	688
	689	sriov_disable(dev);
	690	}
	691	EXPORT_SYMBOL_GPL(pci_disable_sriov);
74bb1bcc YZ	692
	693	/**
	694	* pci_sriov_migration - notify SR-IOV core of Virtual Function Migration
	695	* @dev: the PCI device
	696	*
	697	* Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not.
	698	*
	699	* Physical Function driver is responsible to register IRQ handler using
	700	* VF Migration Interrupt Message Number, and call this function when the
	701	* interrupt is generated by the hardware.
	702	*/
	703	irqreturn_t pci_sriov_migration(struct pci_dev *dev)
	704	{
	705	if (!dev->is_physfn)
	706	return IRQ_NONE;
	707
	708	return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE;
	709	}
	710	EXPORT_SYMBOL_GPL(pci_sriov_migration);
302b4215	711
fb8a0d9d WM	712	/**
	713	* pci_num_vf - return number of VFs associated with a PF device_release_driver
	714	* @dev: the PCI device
	715	*
	716	* Returns number of VFs, or 0 if SR-IOV is not enabled.
	717	*/
	718	int pci_num_vf(struct pci_dev *dev)
	719	{
	720	if (!dev \|\| !dev->is_physfn)
	721	return 0;
	722	else
	723	return dev->sriov->nr_virtfn;
	724	}
	725	EXPORT_SYMBOL_GPL(pci_num_vf);