mirror-linux/drivers/virt/coco/tsm-core.c

164 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/tsm.h>
#include <linux/pci.h>
#include <linux/rwsem.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/cleanup.h>
#include <linux/pci-tsm.h>
#include <linux/pci-ide.h>
static struct class *tsm_class;
static DECLARE_RWSEM(tsm_rwsem);
static DEFINE_IDA(tsm_ida);
static int match_id(struct device *dev, const void *data)
{
struct tsm_dev *tsm_dev = container_of(dev, struct tsm_dev, dev);
int id = *(const int *)data;
return tsm_dev->id == id;
}
struct tsm_dev *find_tsm_dev(int id)
{
struct device *dev = class_find_device(tsm_class, NULL, &id, match_id);
if (!dev)
return NULL;
return container_of(dev, struct tsm_dev, dev);
}
static struct tsm_dev *alloc_tsm_dev(struct device *parent)
{
struct device *dev;
int id;
struct tsm_dev *tsm_dev __free(kfree) =
kzalloc(sizeof(*tsm_dev), GFP_KERNEL);
if (!tsm_dev)
return ERR_PTR(-ENOMEM);
id = ida_alloc(&tsm_ida, GFP_KERNEL);
if (id < 0)
return ERR_PTR(id);
tsm_dev->id = id;
dev = &tsm_dev->dev;
dev->parent = parent;
dev->class = tsm_class;
device_initialize(dev);
return no_free_ptr(tsm_dev);
}
static struct tsm_dev *tsm_register_pci_or_reset(struct tsm_dev *tsm_dev,
struct pci_tsm_ops *pci_ops)
{
int rc;
if (!pci_ops)
return tsm_dev;
tsm_dev->pci_ops = pci_ops;
rc = pci_tsm_register(tsm_dev);
if (rc) {
dev_err(tsm_dev->dev.parent,
"PCI/TSM registration failure: %d\n", rc);
device_unregister(&tsm_dev->dev);
return ERR_PTR(rc);
}
/* Notify TSM userspace that PCI/TSM operations are now possible */
kobject_uevent(&tsm_dev->dev.kobj, KOBJ_CHANGE);
return tsm_dev;
}
struct tsm_dev *tsm_register(struct device *parent, struct pci_tsm_ops *pci_ops)
{
struct tsm_dev *tsm_dev __free(put_tsm_dev) = alloc_tsm_dev(parent);
struct device *dev;
int rc;
if (IS_ERR(tsm_dev))
return tsm_dev;
dev = &tsm_dev->dev;
rc = dev_set_name(dev, "tsm%d", tsm_dev->id);
if (rc)
return ERR_PTR(rc);
rc = device_add(dev);
if (rc)
return ERR_PTR(rc);
return tsm_register_pci_or_reset(no_free_ptr(tsm_dev), pci_ops);
}
EXPORT_SYMBOL_GPL(tsm_register);
void tsm_unregister(struct tsm_dev *tsm_dev)
{
if (tsm_dev->pci_ops)
pci_tsm_unregister(tsm_dev);
device_unregister(&tsm_dev->dev);
}
EXPORT_SYMBOL_GPL(tsm_unregister);
/* must be invoked between tsm_register / tsm_unregister */
int tsm_ide_stream_register(struct pci_ide *ide)
{
struct pci_dev *pdev = ide->pdev;
struct pci_tsm *tsm = pdev->tsm;
struct tsm_dev *tsm_dev = tsm->tsm_dev;
int rc;
rc = sysfs_create_link(&tsm_dev->dev.kobj, &pdev->dev.kobj, ide->name);
if (rc)
return rc;
ide->tsm_dev = tsm_dev;
return 0;
}
EXPORT_SYMBOL_GPL(tsm_ide_stream_register);
void tsm_ide_stream_unregister(struct pci_ide *ide)
{
struct tsm_dev *tsm_dev = ide->tsm_dev;
ide->tsm_dev = NULL;
sysfs_remove_link(&tsm_dev->dev.kobj, ide->name);
}
EXPORT_SYMBOL_GPL(tsm_ide_stream_unregister);
static void tsm_release(struct device *dev)
{
struct tsm_dev *tsm_dev = container_of(dev, typeof(*tsm_dev), dev);
ida_free(&tsm_ida, tsm_dev->id);
kfree(tsm_dev);
}
static int __init tsm_init(void)
{
tsm_class = class_create("tsm");
if (IS_ERR(tsm_class))
return PTR_ERR(tsm_class);
tsm_class->dev_release = tsm_release;
return 0;
}
module_init(tsm_init)
static void __exit tsm_exit(void)
{
class_destroy(tsm_class);
}
module_exit(tsm_exit)
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("TEE Security Manager Class Device");