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/pci.h>
8 #include <linux/rwsem.h>
9 #include <linux/device.h>
10 #include <linux/module.h>
11 #include <linux/cleanup.h>
12 #include <linux/pci-tsm.h>
13 #include <linux/pci-ide.h>
14
15 static struct class *tsm_class;
16 static DECLARE_RWSEM(tsm_rwsem);
17 static DEFINE_IDA(tsm_ida);
18
match_id(struct device * dev,const void * data)19 static int match_id(struct device *dev, const void *data)
20 {
21 struct tsm_dev *tsm_dev = container_of(dev, struct tsm_dev, dev);
22 int id = *(const int *)data;
23
24 return tsm_dev->id == id;
25 }
26
find_tsm_dev(int id)27 struct tsm_dev *find_tsm_dev(int id)
28 {
29 struct device *dev = class_find_device(tsm_class, NULL, &id, match_id);
30
31 if (!dev)
32 return NULL;
33 return container_of(dev, struct tsm_dev, dev);
34 }
35
alloc_tsm_dev(struct device * parent)36 static struct tsm_dev *alloc_tsm_dev(struct device *parent)
37 {
38 struct device *dev;
39 int id;
40
41 struct tsm_dev *tsm_dev __free(kfree) =
42 kzalloc(sizeof(*tsm_dev), GFP_KERNEL);
43 if (!tsm_dev)
44 return ERR_PTR(-ENOMEM);
45
46 id = ida_alloc(&tsm_ida, GFP_KERNEL);
47 if (id < 0)
48 return ERR_PTR(id);
49
50 tsm_dev->id = id;
51 dev = &tsm_dev->dev;
52 dev->parent = parent;
53 dev->class = tsm_class;
54 device_initialize(dev);
55
56 return no_free_ptr(tsm_dev);
57 }
58
tsm_register_pci_or_reset(struct tsm_dev * tsm_dev,struct pci_tsm_ops * pci_ops)59 static struct tsm_dev *tsm_register_pci_or_reset(struct tsm_dev *tsm_dev,
60 struct pci_tsm_ops *pci_ops)
61 {
62 int rc;
63
64 if (!pci_ops)
65 return tsm_dev;
66
67 tsm_dev->pci_ops = pci_ops;
68 rc = pci_tsm_register(tsm_dev);
69 if (rc) {
70 dev_err(tsm_dev->dev.parent,
71 "PCI/TSM registration failure: %d\n", rc);
72 device_unregister(&tsm_dev->dev);
73 return ERR_PTR(rc);
74 }
75
76 /* Notify TSM userspace that PCI/TSM operations are now possible */
77 kobject_uevent(&tsm_dev->dev.kobj, KOBJ_CHANGE);
78 return tsm_dev;
79 }
80
tsm_register(struct device * parent,struct pci_tsm_ops * pci_ops)81 struct tsm_dev *tsm_register(struct device *parent, struct pci_tsm_ops *pci_ops)
82 {
83 struct tsm_dev *tsm_dev __free(put_tsm_dev) = alloc_tsm_dev(parent);
84 struct device *dev;
85 int rc;
86
87 if (IS_ERR(tsm_dev))
88 return tsm_dev;
89
90 dev = &tsm_dev->dev;
91 rc = dev_set_name(dev, "tsm%d", tsm_dev->id);
92 if (rc)
93 return ERR_PTR(rc);
94
95 rc = device_add(dev);
96 if (rc)
97 return ERR_PTR(rc);
98
99 return tsm_register_pci_or_reset(no_free_ptr(tsm_dev), pci_ops);
100 }
101 EXPORT_SYMBOL_GPL(tsm_register);
102
tsm_unregister(struct tsm_dev * tsm_dev)103 void tsm_unregister(struct tsm_dev *tsm_dev)
104 {
105 if (tsm_dev->pci_ops)
106 pci_tsm_unregister(tsm_dev);
107 device_unregister(&tsm_dev->dev);
108 }
109 EXPORT_SYMBOL_GPL(tsm_unregister);
110
111 /* must be invoked between tsm_register / tsm_unregister */
tsm_ide_stream_register(struct pci_ide * ide)112 int tsm_ide_stream_register(struct pci_ide *ide)
113 {
114 struct pci_dev *pdev = ide->pdev;
115 struct pci_tsm *tsm = pdev->tsm;
116 struct tsm_dev *tsm_dev = tsm->tsm_dev;
117 int rc;
118
119 rc = sysfs_create_link(&tsm_dev->dev.kobj, &pdev->dev.kobj, ide->name);
120 if (rc)
121 return rc;
122
123 ide->tsm_dev = tsm_dev;
124 return 0;
125 }
126 EXPORT_SYMBOL_GPL(tsm_ide_stream_register);
127
tsm_ide_stream_unregister(struct pci_ide * ide)128 void tsm_ide_stream_unregister(struct pci_ide *ide)
129 {
130 struct tsm_dev *tsm_dev = ide->tsm_dev;
131
132 ide->tsm_dev = NULL;
133 sysfs_remove_link(&tsm_dev->dev.kobj, ide->name);
134 }
135 EXPORT_SYMBOL_GPL(tsm_ide_stream_unregister);
136
tsm_release(struct device * dev)137 static void tsm_release(struct device *dev)
138 {
139 struct tsm_dev *tsm_dev = container_of(dev, typeof(*tsm_dev), dev);
140
141 ida_free(&tsm_ida, tsm_dev->id);
142 kfree(tsm_dev);
143 }
144
tsm_init(void)145 static int __init tsm_init(void)
146 {
147 tsm_class = class_create("tsm");
148 if (IS_ERR(tsm_class))
149 return PTR_ERR(tsm_class);
150
151 tsm_class->dev_release = tsm_release;
152 return 0;
153 }
module_init(tsm_init)154 module_init(tsm_init)
155
156 static void __exit tsm_exit(void)
157 {
158 class_destroy(tsm_class);
159 }
160 module_exit(tsm_exit)
161
162 MODULE_LICENSE("GPL");
163 MODULE_DESCRIPTION("TEE Security Manager Class Device");
164