linux/drivers/xen/pci.c
Cai Huoqing f66edf684e xen/pci: Make use of the helper macro LIST_HEAD()
Replace "struct list_head head = LIST_HEAD_INIT(head)" with
"LIST_HEAD(head)" to simplify the code.

Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220209032842.38818-1-cai.huoqing@linux.dev
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-02-10 11:10:23 +01:00

333 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2009, Intel Corporation.
*
* Author: Weidong Han <weidong.han@intel.com>
*/
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <xen/pci.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"
#ifdef CONFIG_PCI_MMCONFIG
#include <asm/pci_x86.h>
static int xen_mcfg_late(void);
#endif
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
#ifdef CONFIG_PCI_MMCONFIG
static bool pci_mcfg_reserved = false;
/*
* Reserve MCFG areas in Xen on first invocation due to this being
* potentially called from inside of acpi_init immediately after
* MCFG table has been finally parsed.
*/
if (!pci_mcfg_reserved) {
xen_mcfg_late();
pci_mcfg_reserved = true;
}
#endif
if (pci_seg_supported) {
struct {
struct physdev_pci_device_add add;
uint32_t pxm;
} add_ext = {
.add.seg = pci_domain_nr(pci_dev->bus),
.add.bus = pci_dev->bus->number,
.add.devfn = pci_dev->devfn
};
struct physdev_pci_device_add *add = &add_ext.add;
#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 = ACPI_HANDLE(&pci_dev->dev);
#ifdef CONFIG_PCI_IOV
if (!handle && pci_dev->is_virtfn)
handle = ACPI_HANDLE(physfn->bus->bridge);
#endif
if (!handle) {
/*
* This device was not listed in the ACPI name space at
* all. Try to get acpi handle of parent pci bus.
*/
struct pci_bus *pbus;
for (pbus = pci_dev->bus; pbus; pbus = pbus->parent) {
handle = acpi_pci_get_bridge_handle(pbus);
if (handle)
break;
}
}
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);
#ifdef CONFIG_PCI_MMCONFIG
static int xen_mcfg_late(void)
{
struct pci_mmcfg_region *cfg;
int rc;
if (!xen_initial_domain())
return 0;
if ((pci_probe & PCI_PROBE_MMCONF) == 0)
return 0;
if (list_empty(&pci_mmcfg_list))
return 0;
/* Check whether they are in the right area. */
list_for_each_entry(cfg, &pci_mmcfg_list, list) {
struct physdev_pci_mmcfg_reserved r;
r.address = cfg->address;
r.segment = cfg->segment;
r.start_bus = cfg->start_bus;
r.end_bus = cfg->end_bus;
r.flags = XEN_PCI_MMCFG_RESERVED;
rc = HYPERVISOR_physdev_op(PHYSDEVOP_pci_mmcfg_reserved, &r);
switch (rc) {
case 0:
case -ENOSYS:
continue;
default:
pr_warn("Failed to report MMCONFIG reservation"
" state for %s to hypervisor"
" (%d)\n",
cfg->name, rc);
}
}
return 0;
}
#endif
#ifdef CONFIG_XEN_DOM0
struct xen_device_domain_owner {
domid_t domain;
struct pci_dev *dev;
struct list_head list;
};
static DEFINE_SPINLOCK(dev_domain_list_spinlock);
static LIST_HEAD(dev_domain_list);
static struct xen_device_domain_owner *find_device(struct pci_dev *dev)
{
struct xen_device_domain_owner *owner;
list_for_each_entry(owner, &dev_domain_list, list) {
if (owner->dev == dev)
return owner;
}
return NULL;
}
int xen_find_device_domain_owner(struct pci_dev *dev)
{
struct xen_device_domain_owner *owner;
int domain = -ENODEV;
spin_lock(&dev_domain_list_spinlock);
owner = find_device(dev);
if (owner)
domain = owner->domain;
spin_unlock(&dev_domain_list_spinlock);
return domain;
}
EXPORT_SYMBOL_GPL(xen_find_device_domain_owner);
int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain)
{
struct xen_device_domain_owner *owner;
owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL);
if (!owner)
return -ENODEV;
spin_lock(&dev_domain_list_spinlock);
if (find_device(dev)) {
spin_unlock(&dev_domain_list_spinlock);
kfree(owner);
return -EEXIST;
}
owner->domain = domain;
owner->dev = dev;
list_add_tail(&owner->list, &dev_domain_list);
spin_unlock(&dev_domain_list_spinlock);
return 0;
}
EXPORT_SYMBOL_GPL(xen_register_device_domain_owner);
int xen_unregister_device_domain_owner(struct pci_dev *dev)
{
struct xen_device_domain_owner *owner;
spin_lock(&dev_domain_list_spinlock);
owner = find_device(dev);
if (!owner) {
spin_unlock(&dev_domain_list_spinlock);
return -ENODEV;
}
list_del(&owner->list);
spin_unlock(&dev_domain_list_spinlock);
kfree(owner);
return 0;
}
EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner);
#endif