1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2015-2021, Linaro Limited
4 * Copyright (c) 2016, EPAM Systems
5 */
6
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9 #include <linux/crash_dump.h>
10 #include <linux/errno.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/rpmb.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16 #include <linux/tee_core.h>
17 #include <linux/types.h>
18 #include "optee_private.h"
19
20 struct blocking_notifier_head optee_rpmb_intf_added =
21 BLOCKING_NOTIFIER_INIT(optee_rpmb_intf_added);
22
rpmb_add_dev(struct device * dev)23 static int rpmb_add_dev(struct device *dev)
24 {
25 blocking_notifier_call_chain(&optee_rpmb_intf_added, 0,
26 to_rpmb_dev(dev));
27
28 return 0;
29 }
30
31 static struct class_interface rpmb_class_intf = {
32 .add_dev = rpmb_add_dev,
33 };
34
optee_bus_scan_rpmb(struct work_struct * work)35 void optee_bus_scan_rpmb(struct work_struct *work)
36 {
37 struct optee *optee = container_of(work, struct optee,
38 rpmb_scan_bus_work);
39 int ret;
40
41 if (!optee->rpmb_scan_bus_done) {
42 ret = optee_enumerate_devices(PTA_CMD_GET_DEVICES_RPMB);
43 optee->rpmb_scan_bus_done = !ret;
44 if (ret && ret != -ENODEV)
45 pr_info("Scanning for RPMB device: ret %d\n", ret);
46 }
47 }
48
optee_rpmb_intf_rdev(struct notifier_block * intf,unsigned long action,void * data)49 int optee_rpmb_intf_rdev(struct notifier_block *intf, unsigned long action,
50 void *data)
51 {
52 struct optee *optee = container_of(intf, struct optee, rpmb_intf);
53
54 schedule_work(&optee->rpmb_scan_bus_work);
55
56 return 0;
57 }
58
optee_bus_scan(struct work_struct * work)59 static void optee_bus_scan(struct work_struct *work)
60 {
61 WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
62 }
63
rpmb_routing_model_show(struct device * dev,struct device_attribute * attr,char * buf)64 static ssize_t rpmb_routing_model_show(struct device *dev,
65 struct device_attribute *attr, char *buf)
66 {
67 struct optee *optee = dev_get_drvdata(dev);
68 const char *s;
69
70 if (optee->in_kernel_rpmb_routing)
71 s = "kernel";
72 else
73 s = "user";
74
75 return scnprintf(buf, PAGE_SIZE, "%s\n", s);
76 }
77 static DEVICE_ATTR_RO(rpmb_routing_model);
78
79 static struct attribute *optee_dev_attrs[] = {
80 &dev_attr_rpmb_routing_model.attr,
81 NULL
82 };
83
84 ATTRIBUTE_GROUPS(optee_dev);
85
optee_set_dev_group(struct optee * optee)86 void optee_set_dev_group(struct optee *optee)
87 {
88 tee_device_set_dev_groups(optee->teedev, optee_dev_groups);
89 tee_device_set_dev_groups(optee->supp_teedev, optee_dev_groups);
90 }
91
optee_open(struct tee_context * ctx,bool cap_memref_null)92 int optee_open(struct tee_context *ctx, bool cap_memref_null)
93 {
94 struct optee_context_data *ctxdata;
95 struct tee_device *teedev = ctx->teedev;
96 struct optee *optee = tee_get_drvdata(teedev);
97
98 ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
99 if (!ctxdata)
100 return -ENOMEM;
101
102 if (teedev == optee->supp_teedev) {
103 bool busy = true;
104
105 mutex_lock(&optee->supp.mutex);
106 if (!optee->supp.ctx) {
107 busy = false;
108 optee->supp.ctx = ctx;
109 }
110 mutex_unlock(&optee->supp.mutex);
111 if (busy) {
112 kfree(ctxdata);
113 return -EBUSY;
114 }
115
116 if (!optee->scan_bus_done) {
117 INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
118 schedule_work(&optee->scan_bus_work);
119 optee->scan_bus_done = true;
120 }
121 }
122 mutex_init(&ctxdata->mutex);
123 INIT_LIST_HEAD(&ctxdata->sess_list);
124
125 ctx->cap_memref_null = cap_memref_null;
126 ctx->data = ctxdata;
127 return 0;
128 }
129
optee_release_helper(struct tee_context * ctx,int (* close_session)(struct tee_context * ctx,u32 session,bool system_thread))130 static void optee_release_helper(struct tee_context *ctx,
131 int (*close_session)(struct tee_context *ctx,
132 u32 session,
133 bool system_thread))
134 {
135 struct optee_context_data *ctxdata = ctx->data;
136 struct optee_session *sess;
137 struct optee_session *sess_tmp;
138
139 if (!ctxdata)
140 return;
141
142 list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
143 list_node) {
144 list_del(&sess->list_node);
145 close_session(ctx, sess->session_id, sess->use_sys_thread);
146 kfree(sess);
147 }
148 kfree(ctxdata);
149 ctx->data = NULL;
150 }
151
optee_release(struct tee_context * ctx)152 void optee_release(struct tee_context *ctx)
153 {
154 optee_release_helper(ctx, optee_close_session_helper);
155 }
156
optee_release_supp(struct tee_context * ctx)157 void optee_release_supp(struct tee_context *ctx)
158 {
159 struct optee *optee = tee_get_drvdata(ctx->teedev);
160
161 optee_release_helper(ctx, optee_close_session_helper);
162
163 optee_supp_release(&optee->supp);
164 }
165
optee_remove_common(struct optee * optee)166 void optee_remove_common(struct optee *optee)
167 {
168 blocking_notifier_chain_unregister(&optee_rpmb_intf_added,
169 &optee->rpmb_intf);
170 cancel_work_sync(&optee->rpmb_scan_bus_work);
171 /* Unregister OP-TEE specific client devices on TEE bus */
172 optee_unregister_devices();
173
174 optee_notif_uninit(optee);
175 optee_shm_arg_cache_uninit(optee);
176 teedev_close_context(optee->ctx);
177 /*
178 * The two devices have to be unregistered before we can free the
179 * other resources.
180 */
181 tee_device_unregister(optee->supp_teedev);
182 tee_device_unregister(optee->teedev);
183
184 tee_shm_pool_free(optee->pool);
185 optee_supp_uninit(&optee->supp);
186 mutex_destroy(&optee->call_queue.mutex);
187 rpmb_dev_put(optee->rpmb_dev);
188 mutex_destroy(&optee->rpmb_dev_mutex);
189 }
190
191 static int smc_abi_rc;
192 static int ffa_abi_rc;
193 static bool intf_is_regged;
194
optee_core_init(void)195 static int __init optee_core_init(void)
196 {
197 int rc;
198
199 /*
200 * The kernel may have crashed at the same time that all available
201 * secure world threads were suspended and we cannot reschedule the
202 * suspended threads without access to the crashed kernel's wait_queue.
203 * Therefore, we cannot reliably initialize the OP-TEE driver in the
204 * kdump kernel.
205 */
206 if (is_kdump_kernel())
207 return -ENODEV;
208
209 if (IS_REACHABLE(CONFIG_RPMB)) {
210 rc = rpmb_interface_register(&rpmb_class_intf);
211 if (rc)
212 return rc;
213 intf_is_regged = true;
214 }
215
216 smc_abi_rc = optee_smc_abi_register();
217 ffa_abi_rc = optee_ffa_abi_register();
218
219 /* If both failed there's no point with this module */
220 if (smc_abi_rc && ffa_abi_rc) {
221 if (IS_REACHABLE(CONFIG_RPMB)) {
222 rpmb_interface_unregister(&rpmb_class_intf);
223 intf_is_regged = false;
224 }
225 return smc_abi_rc;
226 }
227
228 return 0;
229 }
230 module_init(optee_core_init);
231
optee_core_exit(void)232 static void __exit optee_core_exit(void)
233 {
234 if (IS_REACHABLE(CONFIG_RPMB) && intf_is_regged) {
235 rpmb_interface_unregister(&rpmb_class_intf);
236 intf_is_regged = false;
237 }
238
239 if (!smc_abi_rc)
240 optee_smc_abi_unregister();
241 if (!ffa_abi_rc)
242 optee_ffa_abi_unregister();
243 }
244 module_exit(optee_core_exit);
245
246 MODULE_AUTHOR("Linaro");
247 MODULE_DESCRIPTION("OP-TEE driver");
248 MODULE_VERSION("1.0");
249 MODULE_LICENSE("GPL v2");
250 MODULE_ALIAS("platform:optee");
251