path: root/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/mutex.h>
#include <linux/string.h>
#include <linux/delay.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 <