drivers/tee/optee/core.c

   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/mm.h>
  13 #include <linux/module.h>
  14 #include <linux/slab.h>
  15 #include <linux/string.h>
  16 #include <linux/tee_drv.h>
  17 #include <linux/types.h>
  18 #include <linux/workqueue.h>
  19 #include "optee_private.h"
  20
  21 int optee_pool_op_alloc_helper(struct tee_shm_pool_mgr *poolm,
  22                                struct tee_shm *shm, size_t size,
  23                                int (*shm_register)(struct tee_context *ctx,
  24                                                    struct tee_shm *shm,
  25                                                    struct page **pages,
  26                                                    size_t num_pages,
  27                                                    unsigned long start))
  28 {
  29         unsigned int order = get_order(size);
  30         struct page *page;
  31         int rc = 0;
  32
  33         page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
  34         if (!page)
  35                 return -ENOMEM;
  36
  37         shm->kaddr = page_address(page);
  38         shm->paddr = page_to_phys(page);
  39         shm->size = PAGE_SIZE << order;
  40
  41         if (shm_register) {
  42                 unsigned int nr_pages = 1 << order, i;
  43                 struct page **pages;
  44
  45                 pages = kcalloc(nr_pages, sizeof(*pages), GFP_KERNEL);
  46                 if (!pages) {
  47                         rc = -ENOMEM;
  48                         goto err;
  49                 }
  50
  51                 for (i = 0; i < nr_pages; i++) {
  52                         pages[i] = page;
  53                         page++;
  54                 }
  55
  56                 shm->flags |= TEE_SHM_REGISTER;
  57                 rc = shm_register(shm->ctx, shm, pages, nr_pages,
  58                                   (unsigned long)shm->kaddr);
  59                 kfree(pages);
  60                 if (rc)
  61                         goto err;
  62         }
  63
  64         return 0;
  65
  66 err:
  67         __free_pages(page, order);
  68         return rc;
  69 }
  70
  71 static void optee_bus_scan(struct work_struct *work)
  72 {
  73         WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
  74 }
  75
  76 int optee_open(struct tee_context *ctx, bool cap_memref_null)
  77 {
  78         struct optee_context_data *ctxdata;
  79         struct tee_device *teedev = ctx->teedev;
  80         struct optee *optee = tee_get_drvdata(teedev);
  81
  82         ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
  83         if (!ctxdata)
  84                 return -ENOMEM;
  85
  86         if (teedev == optee->supp_teedev) {
  87                 bool busy = true;
  88
  89                 mutex_lock(&optee->supp.mutex);
  90                 if (!optee->supp.ctx) {
  91                         busy = false;
  92                         optee->supp.ctx = ctx;
  93                 }
  94                 mutex_unlock(&optee->supp.mutex);
  95                 if (busy) {
  96                         kfree(ctxdata);
  97                         return -EBUSY;
  98                 }
  99
 100                 if (!optee->scan_bus_done) {
 101                         INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
 102                         optee->scan_bus_wq = create_workqueue("optee_bus_scan");
 103                         if (!optee->scan_bus_wq) {
 104                                 kfree(ctxdata);
 105                                 return -ECHILD;
 106                         }
 107                         queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
 108                         optee->scan_bus_done = true;
 109                 }
 110         }
 111         mutex_init(&ctxdata->mutex);
 112         INIT_LIST_HEAD(&ctxdata->sess_list);
 113
 114         ctx->cap_memref_null = cap_memref_null;
 115         ctx->data = ctxdata;
 116         return 0;
 117 }
 118
 119 static void optee_release_helper(struct tee_context *ctx,
 120                                  int (*close_session)(struct tee_context *ctx,
 121                                                       u32 session))
 122 {
 123         struct optee_context_data *ctxdata = ctx->data;
 124         struct optee_session *sess;
 125         struct optee_session *sess_tmp;
 126
 127         if (!ctxdata)
 128                 return;
 129
 130         list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
 131                                  list_node) {
 132                 list_del(&sess->list_node);
 133                 close_session(ctx, sess->session_id);
 134                 kfree(sess);
 135         }
 136         kfree(ctxdata);
 137         ctx->data = NULL;
 138 }
 139
 140 void optee_release(struct tee_context *ctx)
 141 {
 142         optee_release_helper(ctx, optee_close_session_helper);
 143 }
 144
 145 void optee_release_supp(struct tee_context *ctx)
 146 {
 147         struct optee *optee = tee_get_drvdata(ctx->teedev);
 148
 149         optee_release_helper(ctx, optee_close_session_helper);
 150         if (optee->scan_bus_wq) {
 151                 destroy_workqueue(optee->scan_bus_wq);
 152                 optee->scan_bus_wq = NULL;
 153         }
 154         optee_supp_release(&optee->supp);
 155 }
 156
 157 void optee_remove_common(struct optee *optee)
 158 {
 159         /* Unregister OP-TEE specific client devices on TEE bus */
 160         optee_unregister_devices();
 161
 162         optee_notif_uninit(optee);
 163         /*
 164          * The two devices have to be unregistered before we can free the
 165          * other resources.
 166          */
 167         tee_device_unregister(optee->supp_teedev);
 168         tee_device_unregister(optee->teedev);
 169
 170         tee_shm_pool_free(optee->pool);
 171         optee_supp_uninit(&optee->supp);
 172         mutex_destroy(&optee->call_queue.mutex);
 173 }
 174
 175 static int smc_abi_rc;
 176 static int ffa_abi_rc;
 177
 178 static int optee_core_init(void)
 179 {
 180         /*
 181          * The kernel may have crashed at the same time that all available
 182          * secure world threads were suspended and we cannot reschedule the
 183          * suspended threads without access to the crashed kernel's wait_queue.
 184          * Therefore, we cannot reliably initialize the OP-TEE driver in the
 185          * kdump kernel.
 186          */
 187         if (is_kdump_kernel())
 188                 return -ENODEV;
 189
 190         smc_abi_rc = optee_smc_abi_register();
 191         ffa_abi_rc = optee_ffa_abi_register();
 192
 193         /* If both failed there's no point with this module */
 194         if (smc_abi_rc && ffa_abi_rc)
 195                 return smc_abi_rc;
 196         return 0;
 197 }
 198 module_init(optee_core_init);
 199
 200 static void optee_core_exit(void)
 201 {
 202         if (!smc_abi_rc)
 203                 optee_smc_abi_unregister();
 204         if (!ffa_abi_rc)
 205                 optee_ffa_abi_unregister();
 206 }
 207 module_exit(optee_core_exit);
 208
 209 MODULE_AUTHOR("Linaro");
 210 MODULE_DESCRIPTION("OP-TEE driver");
 211 MODULE_VERSION("1.0");
 212 MODULE_LICENSE("GPL v2");
 213 MODULE_ALIAS("platform:optee");