124 строки
2.5 KiB
C
124 строки
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* MDEV driver
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*
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* Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
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* Author: Neo Jia <cjia@nvidia.com>
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* Kirti Wankhede <kwankhede@nvidia.com>
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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/mdev.h>
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#include "mdev_private.h"
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static int mdev_attach_iommu(struct mdev_device *mdev)
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{
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int ret;
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struct iommu_group *group;
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group = iommu_group_alloc();
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if (IS_ERR(group))
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return PTR_ERR(group);
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ret = iommu_group_add_device(group, &mdev->dev);
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if (!ret)
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dev_info(&mdev->dev, "MDEV: group_id = %d\n",
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iommu_group_id(group));
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iommu_group_put(group);
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return ret;
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}
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static void mdev_detach_iommu(struct mdev_device *mdev)
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{
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iommu_group_remove_device(&mdev->dev);
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dev_info(&mdev->dev, "MDEV: detaching iommu\n");
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}
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static int mdev_probe(struct device *dev)
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{
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struct mdev_driver *drv =
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container_of(dev->driver, struct mdev_driver, driver);
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struct mdev_device *mdev = to_mdev_device(dev);
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int ret;
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ret = mdev_attach_iommu(mdev);
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if (ret)
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return ret;
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if (drv->probe) {
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ret = drv->probe(mdev);
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if (ret)
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mdev_detach_iommu(mdev);
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}
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return ret;
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}
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static void mdev_remove(struct device *dev)
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{
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struct mdev_driver *drv =
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container_of(dev->driver, struct mdev_driver, driver);
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struct mdev_device *mdev = to_mdev_device(dev);
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if (drv->remove)
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drv->remove(mdev);
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mdev_detach_iommu(mdev);
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}
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static int mdev_match(struct device *dev, struct device_driver *drv)
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{
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/*
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* No drivers automatically match. Drivers are only bound by explicit
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* device_driver_attach()
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*/
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return 0;
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}
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struct bus_type mdev_bus_type = {
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.name = "mdev",
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.probe = mdev_probe,
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.remove = mdev_remove,
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.match = mdev_match,
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};
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EXPORT_SYMBOL_GPL(mdev_bus_type);
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/**
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* mdev_register_driver - register a new MDEV driver
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* @drv: the driver to register
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*
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* Returns a negative value on error, otherwise 0.
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**/
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int mdev_register_driver(struct mdev_driver *drv)
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{
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/* initialize common driver fields */
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drv->driver.bus = &mdev_bus_type;
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/* register with core */
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return driver_register(&drv->driver);
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}
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EXPORT_SYMBOL(mdev_register_driver);
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/*
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* mdev_unregister_driver - unregister MDEV driver
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* @drv: the driver to unregister
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*/
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void mdev_unregister_driver(struct mdev_driver *drv)
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{
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driver_unregister(&drv->driver);
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}
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EXPORT_SYMBOL(mdev_unregister_driver);
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int mdev_bus_register(void)
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{
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return bus_register(&mdev_bus_type);
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}
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void mdev_bus_unregister(void)
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{
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bus_unregister(&mdev_bus_type);
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}
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