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135 lines
3.1 KiB
135 lines
3.1 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* IOMMU sysfs class support |
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* |
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* Copyright (C) 2014 Red Hat, Inc. All rights reserved. |
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* Author: Alex Williamson <[email protected]> |
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*/ |
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#include <linux/device.h> |
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#include <linux/iommu.h> |
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#include <linux/init.h> |
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#include <linux/slab.h> |
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/* |
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* We provide a common class "devices" group which initially has no attributes. |
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* As devices are added to the IOMMU, we'll add links to the group. |
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*/ |
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static struct attribute *devices_attr[] = { |
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NULL, |
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}; |
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static const struct attribute_group devices_attr_group = { |
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.name = "devices", |
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.attrs = devices_attr, |
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}; |
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static const struct attribute_group *dev_groups[] = { |
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&devices_attr_group, |
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NULL, |
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}; |
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static void release_device(struct device *dev) |
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{ |
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kfree(dev); |
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} |
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static struct class iommu_class = { |
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.name = "iommu", |
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.dev_release = release_device, |
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.dev_groups = dev_groups, |
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}; |
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static int __init iommu_dev_init(void) |
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{ |
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return class_register(&iommu_class); |
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} |
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postcore_initcall(iommu_dev_init); |
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/* |
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* Init the struct device for the IOMMU. IOMMU specific attributes can |
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* be provided as an attribute group, allowing a unique namespace per |
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* IOMMU type. |
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*/ |
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int iommu_device_sysfs_add(struct iommu_device *iommu, |
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struct device *parent, |
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const struct attribute_group **groups, |
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const char *fmt, ...) |
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{ |
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va_list vargs; |
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int ret; |
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iommu->dev = kzalloc(sizeof(*iommu->dev), GFP_KERNEL); |
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if (!iommu->dev) |
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return -ENOMEM; |
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device_initialize(iommu->dev); |
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iommu->dev->class = &iommu_class; |
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iommu->dev->parent = parent; |
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iommu->dev->groups = groups; |
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va_start(vargs, fmt); |
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ret = kobject_set_name_vargs(&iommu->dev->kobj, fmt, vargs); |
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va_end(vargs); |
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if (ret) |
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goto error; |
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ret = device_add(iommu->dev); |
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if (ret) |
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goto error; |
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dev_set_drvdata(iommu->dev, iommu); |
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return 0; |
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error: |
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put_device(iommu->dev); |
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(iommu_device_sysfs_add); |
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void iommu_device_sysfs_remove(struct iommu_device *iommu) |
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{ |
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dev_set_drvdata(iommu->dev, NULL); |
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device_unregister(iommu->dev); |
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iommu->dev = NULL; |
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} |
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EXPORT_SYMBOL_GPL(iommu_device_sysfs_remove); |
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/* |
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* IOMMU drivers can indicate a device is managed by a given IOMMU using |
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* this interface. A link to the device will be created in the "devices" |
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* directory of the IOMMU device in sysfs and an "iommu" link will be |
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* created under the linked device, pointing back at the IOMMU device. |
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*/ |
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int iommu_device_link(struct iommu_device *iommu, struct device *link) |
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{ |
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int ret; |
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if (!iommu || IS_ERR(iommu)) |
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return -ENODEV; |
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ret = sysfs_add_link_to_group(&iommu->dev->kobj, "devices", |
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&link->kobj, dev_name(link)); |
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if (ret) |
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return ret; |
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ret = sysfs_create_link_nowarn(&link->kobj, &iommu->dev->kobj, "iommu"); |
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if (ret) |
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sysfs_remove_link_from_group(&iommu->dev->kobj, "devices", |
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dev_name(link)); |
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(iommu_device_link); |
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void iommu_device_unlink(struct iommu_device *iommu, struct device *link) |
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{ |
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if (!iommu || IS_ERR(iommu)) |
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return; |
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sysfs_remove_link(&link->kobj, "iommu"); |
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sysfs_remove_link_from_group(&iommu->dev->kobj, "devices", dev_name(link)); |
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} |
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EXPORT_SYMBOL_GPL(iommu_device_unlink);
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