From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/iommu/iommu-sysfs.c | 127 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 drivers/iommu/iommu-sysfs.c (limited to 'drivers/iommu/iommu-sysfs.c') diff --git a/drivers/iommu/iommu-sysfs.c b/drivers/iommu/iommu-sysfs.c new file mode 100644 index 0000000000..cbe378c34b --- /dev/null +++ b/drivers/iommu/iommu-sysfs.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * IOMMU sysfs class support + * + * Copyright (C) 2014 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson + */ + +#include +#include +#include +#include + +/* + * 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 devices_attr_group = { + .name = "devices", + .attrs = devices_attr, +}; + +static const struct attribute_group *dev_groups[] = { + &devices_attr_group, + NULL, +}; + +static void release_device(struct device *dev) +{ + kfree(dev); +} + +static struct class iommu_class = { + .name = "iommu", + .dev_release = release_device, + .dev_groups = dev_groups, +}; + +static int __init iommu_dev_init(void) +{ + return class_register(&iommu_class); +} +postcore_initcall(iommu_dev_init); + +/* + * Init the struct device for the IOMMU. IOMMU specific attributes can + * be provided as an attribute group, allowing a unique namespace per + * IOMMU type. + */ +int iommu_device_sysfs_add(struct iommu_device *iommu, + struct device *parent, + const struct attribute_group **groups, + const char *fmt, ...) +{ + va_list vargs; + int ret; + + iommu->dev = kzalloc(sizeof(*iommu->dev), GFP_KERNEL); + if (!iommu->dev) + return -ENOMEM; + + device_initialize(iommu->dev); + + iommu->dev->class = &iommu_class; + iommu->dev->parent = parent; + iommu->dev->groups = groups; + + va_start(vargs, fmt); + ret = kobject_set_name_vargs(&iommu->dev->kobj, fmt, vargs); + va_end(vargs); + if (ret) + goto error; + + ret = device_add(iommu->dev); + if (ret) + goto error; + + dev_set_drvdata(iommu->dev, iommu); + + return 0; + +error: + put_device(iommu->dev); + return ret; +} +EXPORT_SYMBOL_GPL(iommu_device_sysfs_add); + +void iommu_device_sysfs_remove(struct iommu_device *iommu) +{ + dev_set_drvdata(iommu->dev, NULL); + device_unregister(iommu->dev); + iommu->dev = NULL; +} +EXPORT_SYMBOL_GPL(iommu_device_sysfs_remove); + +/* + * 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 iommu_device *iommu, struct device *link) +{ + int ret; + + ret = sysfs_add_link_to_group(&iommu->dev->kobj, "devices", + &link->kobj, dev_name(link)); + if (ret) + return ret; + + ret = sysfs_create_link_nowarn(&link->kobj, &iommu->dev->kobj, "iommu"); + if (ret) + sysfs_remove_link_from_group(&iommu->dev->kobj, "devices", + dev_name(link)); + + return ret; +} + +void iommu_device_unlink(struct iommu_device *iommu, struct device *link) +{ + sysfs_remove_link(&link->kobj, "iommu"); + sysfs_remove_link_from_group(&iommu->dev->kobj, "devices", dev_name(link)); +} -- cgit v1.2.3