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 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 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 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_obj(*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 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 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 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); 106 107 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 } 114 115 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 } 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