1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */
3
4 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
5
6 #include <linux/tsm.h>
7 #include <linux/device.h>
8 #include <linux/module.h>
9 #include <linux/cleanup.h>
10 #include <linux/pci-tsm.h>
11
12 static struct class *tsm_class;
13 static DEFINE_IDA(tsm_ida);
14
match_id(struct device * dev,const void * data)15 static int match_id(struct device *dev, const void *data)
16 {
17 struct tsm_dev *tsm_dev = container_of(dev, struct tsm_dev, dev);
18 int id = *(const int *)data;
19
20 return tsm_dev->id == id;
21 }
22
find_tsm_dev(int id)23 struct tsm_dev *find_tsm_dev(int id)
24 {
25 struct device *dev = class_find_device(tsm_class, NULL, &id, match_id);
26
27 if (!dev)
28 return NULL;
29 return container_of(dev, struct tsm_dev, dev);
30 }
31
alloc_tsm_dev(struct device * parent)32 static struct tsm_dev *alloc_tsm_dev(struct device *parent)
33 {
34 struct device *dev;
35 int id;
36
37 struct tsm_dev *tsm_dev __free(kfree) =
38 kzalloc(sizeof(*tsm_dev), GFP_KERNEL);
39 if (!tsm_dev)
40 return ERR_PTR(-ENOMEM);
41
42 id = ida_alloc(&tsm_ida, GFP_KERNEL);
43 if (id < 0)
44 return ERR_PTR(id);
45
46 tsm_dev->id = id;
47 dev = &tsm_dev->dev;
48 dev->parent = parent;
49 dev->class = tsm_class;
50 device_initialize(dev);
51
52 return no_free_ptr(tsm_dev);
53 }
54
tsm_register_pci_or_reset(struct tsm_dev * tsm_dev,struct pci_tsm_ops * pci_ops)55 static struct tsm_dev *tsm_register_pci_or_reset(struct tsm_dev *tsm_dev,
56 struct pci_tsm_ops *pci_ops)
57 {
58 int rc;
59
60 if (!pci_ops)
61 return tsm_dev;
62
63 tsm_dev->pci_ops = pci_ops;
64 rc = pci_tsm_register(tsm_dev);
65 if (rc) {
66 dev_err(tsm_dev->dev.parent,
67 "PCI/TSM registration failure: %d\n", rc);
68 device_unregister(&tsm_dev->dev);
69 return ERR_PTR(rc);
70 }
71
72 /* Notify TSM userspace that PCI/TSM operations are now possible */
73 kobject_uevent(&tsm_dev->dev.kobj, KOBJ_CHANGE);
74 return tsm_dev;
75 }
76
tsm_register(struct device * parent,struct pci_tsm_ops * pci_ops)77 struct tsm_dev *tsm_register(struct device *parent, struct pci_tsm_ops *pci_ops)
78 {
79 struct tsm_dev *tsm_dev __free(put_tsm_dev) = alloc_tsm_dev(parent);
80 struct device *dev;
81 int rc;
82
83 if (IS_ERR(tsm_dev))
84 return tsm_dev;
85
86 dev = &tsm_dev->dev;
87 rc = dev_set_name(dev, "tsm%d", tsm_dev->id);
88 if (rc)
89 return ERR_PTR(rc);
90
91 rc = device_add(dev);
92 if (rc)
93 return ERR_PTR(rc);
94
95 return tsm_register_pci_or_reset(no_free_ptr(tsm_dev), pci_ops);
96 }
97 EXPORT_SYMBOL_GPL(tsm_register);
98
tsm_unregister(struct tsm_dev * tsm_dev)99 void tsm_unregister(struct tsm_dev *tsm_dev)
100 {
101 if (tsm_dev->pci_ops)
102 pci_tsm_unregister(tsm_dev);
103 device_unregister(&tsm_dev->dev);
104 }
105 EXPORT_SYMBOL_GPL(tsm_unregister);
106
tsm_release(struct device * dev)107 static void tsm_release(struct device *dev)
108 {
109 struct tsm_dev *tsm_dev = container_of(dev, typeof(*tsm_dev), dev);
110
111 ida_free(&tsm_ida, tsm_dev->id);
112 kfree(tsm_dev);
113 }
114
tsm_init(void)115 static int __init tsm_init(void)
116 {
117 tsm_class = class_create("tsm");
118 if (IS_ERR(tsm_class))
119 return PTR_ERR(tsm_class);
120
121 tsm_class->dev_release = tsm_release;
122 return 0;
123 }
module_init(tsm_init)124 module_init(tsm_init)
125
126 static void __exit tsm_exit(void)
127 {
128 class_destroy(tsm_class);
129 }
130 module_exit(tsm_exit)
131
132 MODULE_LICENSE("GPL");
133 MODULE_DESCRIPTION("TEE Security Manager Class Device");
134