linux/drivers/xen/pci.c
Zhang, Yang Z 780dbcd0ee xen/pci: Check for PCI bridge before using it.
Some SR-IOV devices may use more than one bus number, but there is no real bridges
because that have internal routing mechanism. So need to check whether the bridge is
existing before using it.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-30 10:16:35 -04:00

194 lines
4.7 KiB
C

/*
* Copyright (c) 2009, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Author: Weidong Han <weidong.han@intel.com>
*/
#include <linux/pci.h>
#include <linux/acpi.h>
#include <xen/xen.h>
#include <xen/interface/physdev.h>
#include <xen/interface/xen.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include "../pci/pci.h"
static bool __read_mostly pci_seg_supported = true;
static int xen_add_device(struct device *dev)
{
int r;
struct pci_dev *pci_dev = to_pci_dev(dev);
#ifdef CONFIG_PCI_IOV
struct pci_dev *physfn = pci_dev->physfn;
#endif
if (pci_seg_supported) {
struct physdev_pci_device_add add = {
.seg = pci_domain_nr(pci_dev->bus),
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn
};
#ifdef CONFIG_ACPI
acpi_handle handle;
#endif
#ifdef CONFIG_PCI_IOV
if (pci_dev->is_virtfn) {
add.flags = XEN_PCI_DEV_VIRTFN;
add.physfn.bus = physfn->bus->number;
add.physfn.devfn = physfn->devfn;
} else
#endif
if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
add.flags = XEN_PCI_DEV_EXTFN;
#ifdef CONFIG_ACPI
handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
if (!handle && pci_dev->bus->bridge)
handle = DEVICE_ACPI_HANDLE(pci_dev->bus->bridge);
#ifdef CONFIG_PCI_IOV
if (!handle && pci_dev->is_virtfn)
handle = DEVICE_ACPI_HANDLE(physfn->bus->bridge);
#endif
if (handle) {
acpi_status status;
do {
unsigned long long pxm;
status = acpi_evaluate_integer(handle, "_PXM",
NULL, &pxm);
if (ACPI_SUCCESS(status)) {
add.optarr[0] = pxm;
add.flags |= XEN_PCI_DEV_PXM;
break;
}
status = acpi_get_parent(handle, &handle);
} while (ACPI_SUCCESS(status));
}
#endif /* CONFIG_ACPI */
r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
if (r != -ENOSYS)
return r;
pci_seg_supported = false;
}
if (pci_domain_nr(pci_dev->bus))
r = -ENOSYS;
#ifdef CONFIG_PCI_IOV
else if (pci_dev->is_virtfn) {
struct physdev_manage_pci_ext manage_pci_ext = {
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn,
.is_virtfn = 1,
.physfn.bus = physfn->bus->number,
.physfn.devfn = physfn->devfn,
};
r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
&manage_pci_ext);
}
#endif
else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
struct physdev_manage_pci_ext manage_pci_ext = {
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn,
.is_extfn = 1,
};
r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
&manage_pci_ext);
} else {
struct physdev_manage_pci manage_pci = {
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn,
};
r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
&manage_pci);
}
return r;
}
static int xen_remove_device(struct device *dev)
{
int r;
struct pci_dev *pci_dev = to_pci_dev(dev);
if (pci_seg_supported) {
struct physdev_pci_device device = {
.seg = pci_domain_nr(pci_dev->bus),
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn
};
r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
&device);
} else if (pci_domain_nr(pci_dev->bus))
r = -ENOSYS;
else {
struct physdev_manage_pci manage_pci = {
.bus = pci_dev->bus->number,
.devfn = pci_dev->devfn
};
r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
&manage_pci);
}
return r;
}
static int xen_pci_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
int r = 0;
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
r = xen_add_device(dev);
break;
case BUS_NOTIFY_DEL_DEVICE:
r = xen_remove_device(dev);
break;
default:
return NOTIFY_DONE;
}
if (r)
dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
action == BUS_NOTIFY_ADD_DEVICE ? "add" :
(action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
return NOTIFY_OK;
}
static struct notifier_block device_nb = {
.notifier_call = xen_pci_notifier,
};
static int __init register_xen_pci_notifier(void)
{
if (!xen_initial_domain())
return 0;
return bus_register_notifier(&pci_bus_type, &device_nb);
}
arch_initcall(register_xen_pci_notifier);