mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 08:14:15 +08:00
135 lines
3.0 KiB
C
135 lines
3.0 KiB
C
/*
|
|
* IOMMU sysfs class support
|
|
*
|
|
* Copyright (C) 2014 Red Hat, Inc. All rights reserved.
|
|
* Author: Alex Williamson <alex.williamson@redhat.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/iommu.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
|
|
/*
|
|
* We provide a common class "devices" group which initially has no attributes.
|
|
* As devices are added to the IOMMU, we'll add links to the group.
|
|
*/
|
|
static struct attribute *devices_attr[] = {
|
|
NULL,
|
|
};
|
|
|
|
static const struct attribute_group iommu_devices_attr_group = {
|
|
.name = "devices",
|
|
.attrs = devices_attr,
|
|
};
|
|
|
|
static const struct attribute_group *iommu_dev_groups[] = {
|
|
&iommu_devices_attr_group,
|
|
NULL,
|
|
};
|
|
|
|
static void iommu_release_device(struct device *dev)
|
|
{
|
|
kfree(dev);
|
|
}
|
|
|
|
static struct class iommu_class = {
|
|
.name = "iommu",
|
|
.dev_release = iommu_release_device,
|
|
.dev_groups = iommu_dev_groups,
|
|
};
|
|
|
|
static int __init iommu_dev_init(void)
|
|
{
|
|
return class_register(&iommu_class);
|
|
}
|
|
postcore_initcall(iommu_dev_init);
|
|
|
|
/*
|
|
* Create an IOMMU device and return a pointer to it. IOMMU specific
|
|
* attributes can be provided as an attribute group, allowing a unique
|
|
* namespace per IOMMU type.
|
|
*/
|
|
struct device *iommu_device_create(struct device *parent, void *drvdata,
|
|
const struct attribute_group **groups,
|
|
const char *fmt, ...)
|
|
{
|
|
struct device *dev;
|
|
va_list vargs;
|
|
int ret;
|
|
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
if (!dev)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
device_initialize(dev);
|
|
|
|
dev->class = &iommu_class;
|
|
dev->parent = parent;
|
|
dev->groups = groups;
|
|
dev_set_drvdata(dev, drvdata);
|
|
|
|
va_start(vargs, fmt);
|
|
ret = kobject_set_name_vargs(&dev->kobj, fmt, vargs);
|
|
va_end(vargs);
|
|
if (ret)
|
|
goto error;
|
|
|
|
ret = device_add(dev);
|
|
if (ret)
|
|
goto error;
|
|
|
|
return dev;
|
|
|
|
error:
|
|
put_device(dev);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
void iommu_device_destroy(struct device *dev)
|
|
{
|
|
if (!dev || IS_ERR(dev))
|
|
return;
|
|
|
|
device_unregister(dev);
|
|
}
|
|
|
|
/*
|
|
* IOMMU drivers can indicate a device is managed by a given IOMMU using
|
|
* this interface. A link to the device will be created in the "devices"
|
|
* directory of the IOMMU device in sysfs and an "iommu" link will be
|
|
* created under the linked device, pointing back at the IOMMU device.
|
|
*/
|
|
int iommu_device_link(struct device *dev, struct device *link)
|
|
{
|
|
int ret;
|
|
|
|
if (!dev || IS_ERR(dev))
|
|
return -ENODEV;
|
|
|
|
ret = sysfs_add_link_to_group(&dev->kobj, "devices",
|
|
&link->kobj, dev_name(link));
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = sysfs_create_link_nowarn(&link->kobj, &dev->kobj, "iommu");
|
|
if (ret)
|
|
sysfs_remove_link_from_group(&dev->kobj, "devices",
|
|
dev_name(link));
|
|
|
|
return ret;
|
|
}
|
|
|
|
void iommu_device_unlink(struct device *dev, struct device *link)
|
|
{
|
|
if (!dev || IS_ERR(dev))
|
|
return;
|
|
|
|
sysfs_remove_link(&link->kobj, "iommu");
|
|
sysfs_remove_link_from_group(&dev->kobj, "devices", dev_name(link));
|
|
}
|