drivers/tee/optee/rpc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015-2016, Linaro Limited
   4  */
   5
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8 #include <linux/delay.h>
   9 #include <linux/device.h>
  10 #include <linux/slab.h>
  11 #include <linux/tee_drv.h>
  12 #include "optee_private.h"
  13 #include "optee_smc.h"
  14
  15 struct wq_entry {
  16         struct list_head link;
  17         struct completion c;
  18         u32 key;
  19 };
  20
  21 void optee_wait_queue_init(struct optee_wait_queue *priv)
  22 {
  23         mutex_init(&priv->mu);
  24         INIT_LIST_HEAD(&priv->db);
  25 }
  26
  27 void optee_wait_queue_exit(struct optee_wait_queue *priv)
  28 {
  29         mutex_destroy(&priv->mu);
  30 }
  31
  32 static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg)
  33 {
  34         struct timespec64 ts;
  35
  36         if (arg->num_params != 1)
  37                 goto bad;
  38         if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
  39                         OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT)
  40                 goto bad;
  41
  42         ktime_get_real_ts64(&ts);
  43         arg->params[0].u.value.a = ts.tv_sec;
  44         arg->params[0].u.value.b = ts.tv_nsec;
  45
  46         arg->ret = TEEC_SUCCESS;
  47         return;
  48 bad:
  49         arg->ret = TEEC_ERROR_BAD_PARAMETERS;
  50 }
  51
  52 static struct wq_entry *wq_entry_get(struct optee_wait_queue *wq, u32 key)
  53 {
  54         struct wq_entry *w;
  55
  56         mutex_lock(&wq->mu);
  57
  58         list_for_each_entry(w, &wq->db, link)
  59                 if (w->key == key)
  60                         goto out;
  61
  62         w = kmalloc(sizeof(*w), GFP_KERNEL);
  63         if (w) {
  64                 init_completion(&w->c);
  65                 w->key = key;
  66                 list_add_tail(&w->link, &wq->db);
  67         }
  68 out:
  69         mutex_unlock(&wq->mu);
  70         return w;
  71 }
  72
  73 static void wq_sleep(struct optee_wait_queue *wq, u32 key)
  74 {
  75         struct wq_entry *w = wq_entry_get(wq, key);
  76
  77         if (w) {
  78                 wait_for_completion(&w->c);
  79                 mutex_lock(&wq->mu);
  80                 list_del(&w->link);
  81                 mutex_unlock(&wq->mu);
  82                 kfree(w);
  83         }
  84 }
  85
  86 static void wq_wakeup(struct optee_wait_queue *wq, u32 key)
  87 {
  88         struct wq_entry *w = wq_entry_get(wq, key);
  89
  90         if (w)
  91                 complete(&w->c);
  92 }
  93
  94 static void handle_rpc_func_cmd_wq(struct optee *optee,
  95                                    struct optee_msg_arg *arg)
  96 {
  97         if (arg->num_params != 1)
  98                 goto bad;
  99
 100         if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
 101                         OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
 102                 goto bad;
 103
 104         switch (arg->params[0].u.value.a) {
 105         case OPTEE_MSG_RPC_WAIT_QUEUE_SLEEP:
 106                 wq_sleep(&optee->wait_queue, arg->params[0].u.value.b);
 107                 break;
 108         case OPTEE_MSG_RPC_WAIT_QUEUE_WAKEUP:
 109                 wq_wakeup(&optee->wait_queue, arg->params[0].u.value.b);
 110                 break;
 111         default:
 112                 goto bad;
 113         }
 114
 115         arg->ret = TEEC_SUCCESS;
 116         return;
 117 bad:
 118         arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 119 }
 120
 121 static void handle_rpc_func_cmd_wait(struct optee_msg_arg *arg)
 122 {
 123         u32 msec_to_wait;
 124
 125         if (arg->num_params != 1)
 126                 goto bad;
 127
 128         if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
 129                         OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
 130                 goto bad;
 131
 132         msec_to_wait = arg->params[0].u.value.a;
 133
 134         /* Go to interruptible sleep */
 135         msleep_interruptible(msec_to_wait);
 136
 137         arg->ret = TEEC_SUCCESS;
 138         return;
 139 bad:
 140         arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 141 }
 142
 143 static void handle_rpc_supp_cmd(struct tee_context *ctx,
 144                                 struct optee_msg_arg *arg)
 145 {
 146         struct tee_param *params;
 147
 148         arg->ret_origin = TEEC_ORIGIN_COMMS;
 149
 150         params = kmalloc_array(arg->num_params, sizeof(struct tee_param),
 151                                GFP_KERNEL);
 152         if (!params) {
 153                 arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
 154                 return;
 155         }
 156
 157         if (optee_from_msg_param(params, arg->num_params, arg->params)) {
 158                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 159                 goto out;
 160         }
 161
 162         arg->ret = optee_supp_thrd_req(ctx, arg->cmd, arg->num_params, params);
 163
 164         if (optee_to_msg_param(arg->params, arg->num_params, params))
 165                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 166 out:
 167         kfree(params);
 168 }
 169
 170 static struct tee_shm *cmd_alloc_suppl(struct tee_context *ctx, size_t sz)
 171 {
 172         u32 ret;
 173         struct tee_param param;
 174         struct optee *optee = tee_get_drvdata(ctx->teedev);
 175         struct tee_shm *shm;
 176
 177         param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
 178         param.u.value.a = OPTEE_MSG_RPC_SHM_TYPE_APPL;
 179         param.u.value.b = sz;
 180         param.u.value.c = 0;
 181
 182         ret = optee_supp_thrd_req(ctx, OPTEE_MSG_RPC_CMD_SHM_ALLOC, 1, &param);
 183         if (ret)
 184                 return ERR_PTR(-ENOMEM);
 185
 186         mutex_lock(&optee->supp.mutex);
 187         /* Increases count as secure world doesn't have a reference */
 188         shm = tee_shm_get_from_id(optee->supp.ctx, param.u.value.c);
 189         mutex_unlock(&optee->supp.mutex);
 190         return shm;
 191 }
 192
 193 static void handle_rpc_func_cmd_shm_alloc(struct tee_context *ctx,
 194                                           struct optee_msg_arg *arg,
 195                                           struct optee_call_ctx *call_ctx)
 196 {
 197         phys_addr_t pa;
 198         struct tee_shm *shm;
 199         size_t sz;
 200         size_t n;
 201
 202         arg->ret_origin = TEEC_ORIGIN_COMMS;
 203
 204         if (!arg->num_params ||
 205             arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) {
 206                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 207                 return;
 208         }
 209
 210         for (n = 1; n < arg->num_params; n++) {
 211                 if (arg->params[n].attr != OPTEE_MSG_ATTR_TYPE_NONE) {
 212                         arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 213                         return;
 214                 }
 215         }
 216
 217         sz = arg->params[0].u.value.b;
 218         switch (arg->params[0].u.value.a) {
 219         case OPTEE_MSG_RPC_SHM_TYPE_APPL:
 220                 shm = cmd_alloc_suppl(ctx, sz);
 221                 break;
 222         case OPTEE_MSG_RPC_SHM_TYPE_KERNEL:
 223                 shm = tee_shm_alloc(ctx, sz, TEE_SHM_MAPPED);
 224                 break;
 225         default:
 226                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 227                 return;
 228         }
 229
 230         if (IS_ERR(shm)) {
 231                 arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
 232                 return;
 233         }
 234
 235         if (tee_shm_get_pa(shm, 0, &pa)) {
 236                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 237                 goto bad;
 238         }
 239
 240         sz = tee_shm_get_size(shm);
 241
 242         if (tee_shm_is_registered(shm)) {
 243                 struct page **pages;
 244                 u64 *pages_list;
 245                 size_t page_num;
 246
 247                 pages = tee_shm_get_pages(shm, &page_num);
 248                 if (!pages || !page_num) {
 249                         arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
 250                         goto bad;
 251                 }
 252
 253                 pages_list = optee_allocate_pages_list(page_num);
 254                 if (!pages_list) {
 255                         arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
 256                         goto bad;
 257                 }
 258
 259                 call_ctx->pages_list = pages_list;
 260                 call_ctx->num_entries = page_num;
 261
 262                 arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT |
 263                                       OPTEE_MSG_ATTR_NONCONTIG;
 264                 /*
 265                  * In the least bits of u.tmem.buf_ptr we store buffer offset
 266                  * from 4k page, as described in OP-TEE ABI.
 267                  */
 268                 arg->params[0].u.tmem.buf_ptr = virt_to_phys(pages_list) |
 269                         (tee_shm_get_page_offset(shm) &
 270                          (OPTEE_MSG_NONCONTIG_PAGE_SIZE - 1));
 271                 arg->params[0].u.tmem.size = tee_shm_get_size(shm);
 272                 arg->params[0].u.tmem.shm_ref = (unsigned long)shm;
 273
 274                 optee_fill_pages_list(pages_list, pages, page_num,
 275                                       tee_shm_get_page_offset(shm));
 276         } else {
 277                 arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT;
 278                 arg->params[0].u.tmem.buf_ptr = pa;
 279                 arg->params[0].u.tmem.size = sz;
 280                 arg->params[0].u.tmem.shm_ref = (unsigned long)shm;
 281         }
 282
 283         arg->ret = TEEC_SUCCESS;
 284         return;
 285 bad:
 286         tee_shm_free(shm);
 287 }
 288
 289 static void cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm)
 290 {
 291         struct tee_param param;
 292
 293         param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
 294         param.u.value.a = OPTEE_MSG_RPC_SHM_TYPE_APPL;
 295         param.u.value.b = tee_shm_get_id(shm);
 296         param.u.value.c = 0;
 297
 298         /*
 299          * Match the tee_shm_get_from_id() in cmd_alloc_suppl() as secure
 300          * world has released its reference.
 301          *
 302          * It's better to do this before sending the request to supplicant
 303          * as we'd like to let the process doing the initial allocation to
 304          * do release the last reference too in order to avoid stacking
 305          * many pending fput() on the client process. This could otherwise
 306          * happen if secure world does many allocate and free in a single
 307          * invoke.
 308          */
 309         tee_shm_put(shm);
 310
 311         optee_supp_thrd_req(ctx, OPTEE_MSG_RPC_CMD_SHM_FREE, 1, &param);
 312 }
 313
 314 static void handle_rpc_func_cmd_shm_free(struct tee_context *ctx,
 315                                          struct optee_msg_arg *arg)
 316 {
 317         struct tee_shm *shm;
 318
 319         arg->ret_origin = TEEC_ORIGIN_COMMS;
 320
 321         if (arg->num_params != 1 ||
 322             arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) {
 323                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 324                 return;
 325         }
 326
 327         shm = (struct tee_shm *)(unsigned long)arg->params[0].u.value.b;
 328         switch (arg->params[0].u.value.a) {
 329         case OPTEE_MSG_RPC_SHM_TYPE_APPL:
 330                 cmd_free_suppl(ctx, shm);
 331                 break;
 332         case OPTEE_MSG_RPC_SHM_TYPE_KERNEL:
 333                 tee_shm_free(shm);
 334                 break;
 335         default:
 336                 arg->ret = TEEC_ERROR_BAD_PARAMETERS;
 337         }
 338         arg->ret = TEEC_SUCCESS;
 339 }
 340
 341 static void free_pages_list(struct optee_call_ctx *call_ctx)
 342 {
 343         if (call_ctx->pages_list) {
 344                 optee_free_pages_list(call_ctx->pages_list,
 345                                       call_ctx->num_entries);
 346                 call_ctx->pages_list = NULL;
 347                 call_ctx->num_entries = 0;
 348         }
 349 }
 350
 351 void optee_rpc_finalize_call(struct optee_call_ctx *call_ctx)
 352 {
 353         free_pages_list(call_ctx);
 354 }
 355
 356 static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee,
 357                                 struct tee_shm *shm,
 358                                 struct optee_call_ctx *call_ctx)
 359 {
 360         struct optee_msg_arg *arg;
 361
 362         arg = tee_shm_get_va(shm, 0);
 363         if (IS_ERR(arg)) {
 364                 pr_err("%s: tee_shm_get_va %p failed\n", __func__, shm);
 365                 return;
 366         }
 367
 368         switch (arg->cmd) {
 369         case OPTEE_MSG_RPC_CMD_GET_TIME:
 370                 handle_rpc_func_cmd_get_time(arg);
 371                 break;
 372         case OPTEE_MSG_RPC_CMD_WAIT_QUEUE:
 373                 handle_rpc_func_cmd_wq(optee, arg);
 374                 break;
 375         case OPTEE_MSG_RPC_CMD_SUSPEND:
 376                 handle_rpc_func_cmd_wait(arg);
 377                 break;
 378         case OPTEE_MSG_RPC_CMD_SHM_ALLOC:
 379                 free_pages_list(call_ctx);
 380                 handle_rpc_func_cmd_shm_alloc(ctx, arg, call_ctx);
 381                 break;
 382         case OPTEE_MSG_RPC_CMD_SHM_FREE:
 383                 handle_rpc_func_cmd_shm_free(ctx, arg);
 384                 break;
 385         default:
 386                 handle_rpc_supp_cmd(ctx, arg);
 387         }
 388 }
 389
 390 /**
 391  * optee_handle_rpc() - handle RPC from secure world
 392  * @ctx:        context doing the RPC
 393  * @param:      value of registers for the RPC
 394  * @call_ctx:   call context. Preserved during one OP-TEE invocation
 395  *
 396  * Result of RPC is written back into @param.
 397  */
 398 void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param,
 399                       struct optee_call_ctx *call_ctx)
 400 {
 401         struct tee_device *teedev = ctx->teedev;
 402         struct optee *optee = tee_get_drvdata(teedev);
 403         struct tee_shm *shm;
 404         phys_addr_t pa;
 405
 406         switch (OPTEE_SMC_RETURN_GET_RPC_FUNC(param->a0)) {
 407         case OPTEE_SMC_RPC_FUNC_ALLOC:
 408                 shm = tee_shm_alloc(ctx, param->a1, TEE_SHM_MAPPED);
 409                 if (!IS_ERR(shm) && !tee_shm_get_pa(shm, 0, &pa)) {
 410                         reg_pair_from_64(&param->a1, &param->a2, pa);
 411                         reg_pair_from_64(&param->a4, &param->a5,
 412                                          (unsigned long)shm);
 413                 } else {
 414                         param->a1 = 0;
 415                         param->a2 = 0;
 416                         param->a4 = 0;
 417                         param->a5 = 0;
 418                 }
 419                 break;
 420         case OPTEE_SMC_RPC_FUNC_FREE:
 421                 shm = reg_pair_to_ptr(param->a1, param->a2);
 422                 tee_shm_free(shm);
 423                 break;
 424         case OPTEE_SMC_RPC_FUNC_FOREIGN_INTR:
 425                 /*
 426                  * A foreign interrupt was raised while secure world was
 427                  * executing, since they are handled in Linux a dummy RPC is
 428                  * performed to let Linux take the interrupt through the normal
 429                  * vector.
 430                  */
 431                 break;
 432         case OPTEE_SMC_RPC_FUNC_CMD:
 433                 shm = reg_pair_to_ptr(param->a1, param->a2);
 434                 handle_rpc_func_cmd(ctx, optee, shm, call_ctx);
 435                 break;
 436         default:
 437                 pr_warn("Unknown RPC func 0x%x\n",
 438                         (u32)OPTEE_SMC_RETURN_GET_RPC_FUNC(param->a0));
 439                 break;
 440         }
 441
 442         param->a0 = OPTEE_SMC_CALL_RETURN_FROM_RPC;
 443 }