diff options
Diffstat (limited to 'drivers/tee/optee/rpc.c')
-rw-r--r-- | drivers/tee/optee/rpc.c | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c new file mode 100644 index 000000000..b45c73dd3 --- /dev/null +++ b/drivers/tee/optee/rpc.c @@ -0,0 +1,452 @@ +/* + * Copyright (c) 2015-2016, Linaro Limited + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/tee_drv.h> +#include "optee_private.h" +#include "optee_smc.h" + +struct wq_entry { + struct list_head link; + struct completion c; + u32 key; +}; + +void optee_wait_queue_init(struct optee_wait_queue *priv) +{ + mutex_init(&priv->mu); + INIT_LIST_HEAD(&priv->db); +} + +void optee_wait_queue_exit(struct optee_wait_queue *priv) +{ + mutex_destroy(&priv->mu); +} + +static void handle_rpc_func_cmd_get_time(struct optee_msg_arg *arg) +{ + struct timespec64 ts; + + if (arg->num_params != 1) + goto bad; + if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) != + OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT) + goto bad; + + ktime_get_real_ts64(&ts); + arg->params[0].u.value.a = ts.tv_sec; + arg->params[0].u.value.b = ts.tv_nsec; + + arg->ret = TEEC_SUCCESS; + return; +bad: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; +} + +static struct wq_entry *wq_entry_get(struct optee_wait_queue *wq, u32 key) +{ + struct wq_entry *w; + + mutex_lock(&wq->mu); + + list_for_each_entry(w, &wq->db, link) + if (w->key == key) + goto out; + + w = kmalloc(sizeof(*w), GFP_KERNEL); + if (w) { + init_completion(&w->c); + w->key = key; + list_add_tail(&w->link, &wq->db); + } +out: + mutex_unlock(&wq->mu); + return w; +} + +static void wq_sleep(struct optee_wait_queue *wq, u32 key) +{ + struct wq_entry *w = wq_entry_get(wq, key); + + if (w) { + wait_for_completion(&w->c); + mutex_lock(&wq->mu); + list_del(&w->link); + mutex_unlock(&wq->mu); + kfree(w); + } +} + +static void wq_wakeup(struct optee_wait_queue *wq, u32 key) +{ + struct wq_entry *w = wq_entry_get(wq, key); + + if (w) + complete(&w->c); +} + +static void handle_rpc_func_cmd_wq(struct optee *optee, + struct optee_msg_arg *arg) +{ + if (arg->num_params != 1) + goto bad; + + if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) != + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) + goto bad; + + switch (arg->params[0].u.value.a) { + case OPTEE_MSG_RPC_WAIT_QUEUE_SLEEP: + wq_sleep(&optee->wait_queue, arg->params[0].u.value.b); + break; + case OPTEE_MSG_RPC_WAIT_QUEUE_WAKEUP: + wq_wakeup(&optee->wait_queue, arg->params[0].u.value.b); + break; + default: + goto bad; + } + + arg->ret = TEEC_SUCCESS; + return; +bad: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; +} + +static void handle_rpc_func_cmd_wait(struct optee_msg_arg *arg) +{ + u32 msec_to_wait; + + if (arg->num_params != 1) + goto bad; + + if ((arg->params[0].attr & OPTEE_MSG_ATTR_TYPE_MASK) != + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) + goto bad; + + msec_to_wait = arg->params[0].u.value.a; + + /* Go to interruptible sleep */ + msleep_interruptible(msec_to_wait); + + arg->ret = TEEC_SUCCESS; + return; +bad: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; +} + +static void handle_rpc_supp_cmd(struct tee_context *ctx, + struct optee_msg_arg *arg) +{ + struct tee_param *params; + + arg->ret_origin = TEEC_ORIGIN_COMMS; + + params = kmalloc_array(arg->num_params, sizeof(struct tee_param), + GFP_KERNEL); + if (!params) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + return; + } + + if (optee_from_msg_param(params, arg->num_params, arg->params)) { + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + goto out; + } + + arg->ret = optee_supp_thrd_req(ctx, arg->cmd, arg->num_params, params); + + if (optee_to_msg_param(arg->params, arg->num_params, params)) + arg->ret = TEEC_ERROR_BAD_PARAMETERS; +out: + kfree(params); +} + +static struct tee_shm *cmd_alloc_suppl(struct tee_context *ctx, size_t sz) +{ + u32 ret; + struct tee_param param; + struct optee *optee = tee_get_drvdata(ctx->teedev); + struct tee_shm *shm; + + param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT; + param.u.value.a = OPTEE_MSG_RPC_SHM_TYPE_APPL; + param.u.value.b = sz; + param.u.value.c = 0; + + ret = optee_supp_thrd_req(ctx, OPTEE_MSG_RPC_CMD_SHM_ALLOC, 1, ¶m); + if (ret) + return ERR_PTR(-ENOMEM); + + mutex_lock(&optee->supp.mutex); + /* Increases count as secure world doesn't have a reference */ + shm = tee_shm_get_from_id(optee->supp.ctx, param.u.value.c); + mutex_unlock(&optee->supp.mutex); + return shm; +} + +static void handle_rpc_func_cmd_shm_alloc(struct tee_context *ctx, + struct optee_msg_arg *arg, + struct optee_call_ctx *call_ctx) +{ + phys_addr_t pa; + struct tee_shm *shm; + size_t sz; + size_t n; + + arg->ret_origin = TEEC_ORIGIN_COMMS; + + if (!arg->num_params || + arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) { + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + return; + } + + for (n = 1; n < arg->num_params; n++) { + if (arg->params[n].attr != OPTEE_MSG_ATTR_TYPE_NONE) { + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + return; + } + } + + sz = arg->params[0].u.value.b; + switch (arg->params[0].u.value.a) { + case OPTEE_MSG_RPC_SHM_TYPE_APPL: + shm = cmd_alloc_suppl(ctx, sz); + break; + case OPTEE_MSG_RPC_SHM_TYPE_KERNEL: + shm = tee_shm_alloc(ctx, sz, TEE_SHM_MAPPED); + break; + default: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + return; + } + + if (IS_ERR(shm)) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + return; + } + + if (tee_shm_get_pa(shm, 0, &pa)) { + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + goto bad; + } + + sz = tee_shm_get_size(shm); + + if (tee_shm_is_registered(shm)) { + struct page **pages; + u64 *pages_list; + size_t page_num; + + pages = tee_shm_get_pages(shm, &page_num); + if (!pages || !page_num) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + goto bad; + } + + pages_list = optee_allocate_pages_list(page_num); + if (!pages_list) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + goto bad; + } + + call_ctx->pages_list = pages_list; + call_ctx->num_entries = page_num; + + arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT | + OPTEE_MSG_ATTR_NONCONTIG; + /* + * In the least bits of u.tmem.buf_ptr we store buffer offset + * from 4k page, as described in OP-TEE ABI. + */ + arg->params[0].u.tmem.buf_ptr = virt_to_phys(pages_list) | + (tee_shm_get_page_offset(shm) & + (OPTEE_MSG_NONCONTIG_PAGE_SIZE - 1)); + arg->params[0].u.tmem.size = tee_shm_get_size(shm); + arg->params[0].u.tmem.shm_ref = (unsigned long)shm; + + optee_fill_pages_list(pages_list, pages, page_num, + tee_shm_get_page_offset(shm)); + } else { + arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT; + arg->params[0].u.tmem.buf_ptr = pa; + arg->params[0].u.tmem.size = sz; + arg->params[0].u.tmem.shm_ref = (unsigned long)shm; + } + + arg->ret = TEEC_SUCCESS; + return; +bad: + tee_shm_free(shm); +} + +static void cmd_free_suppl(struct tee_context *ctx, struct tee_shm *shm) +{ + struct tee_param param; + + param.attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT; + param.u.value.a = OPTEE_MSG_RPC_SHM_TYPE_APPL; + param.u.value.b = tee_shm_get_id(shm); + param.u.value.c = 0; + + /* + * Match the tee_shm_get_from_id() in cmd_alloc_suppl() as secure + * world has released its reference. + * + * It's better to do this before sending the request to supplicant + * as we'd like to let the process doing the initial allocation to + * do release the last reference too in order to avoid stacking + * many pending fput() on the client process. This could otherwise + * happen if secure world does many allocate and free in a single + * invoke. + */ + tee_shm_put(shm); + + optee_supp_thrd_req(ctx, OPTEE_MSG_RPC_CMD_SHM_FREE, 1, ¶m); +} + +static void handle_rpc_func_cmd_shm_free(struct tee_context *ctx, + struct optee_msg_arg *arg) +{ + struct tee_shm *shm; + + arg->ret_origin = TEEC_ORIGIN_COMMS; + + if (arg->num_params != 1 || + arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) { + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + return; + } + + shm = (struct tee_shm *)(unsigned long)arg->params[0].u.value.b; + switch (arg->params[0].u.value.a) { + case OPTEE_MSG_RPC_SHM_TYPE_APPL: + cmd_free_suppl(ctx, shm); + break; + case OPTEE_MSG_RPC_SHM_TYPE_KERNEL: + tee_shm_free(shm); + break; + default: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + } + arg->ret = TEEC_SUCCESS; +} + +static void free_pages_list(struct optee_call_ctx *call_ctx) +{ + if (call_ctx->pages_list) { + optee_free_pages_list(call_ctx->pages_list, + call_ctx->num_entries); + call_ctx->pages_list = NULL; + call_ctx->num_entries = 0; + } +} + +void optee_rpc_finalize_call(struct optee_call_ctx *call_ctx) +{ + free_pages_list(call_ctx); +} + +static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, + struct tee_shm *shm, + struct optee_call_ctx *call_ctx) +{ + struct optee_msg_arg *arg; + + arg = tee_shm_get_va(shm, 0); + if (IS_ERR(arg)) { + pr_err("%s: tee_shm_get_va %p failed\n", __func__, shm); + return; + } + + switch (arg->cmd) { + case OPTEE_MSG_RPC_CMD_GET_TIME: + handle_rpc_func_cmd_get_time(arg); + break; + case OPTEE_MSG_RPC_CMD_WAIT_QUEUE: + handle_rpc_func_cmd_wq(optee, arg); + break; + case OPTEE_MSG_RPC_CMD_SUSPEND: + handle_rpc_func_cmd_wait(arg); + break; + case OPTEE_MSG_RPC_CMD_SHM_ALLOC: + free_pages_list(call_ctx); + handle_rpc_func_cmd_shm_alloc(ctx, arg, call_ctx); + break; + case OPTEE_MSG_RPC_CMD_SHM_FREE: + handle_rpc_func_cmd_shm_free(ctx, arg); + break; + default: + handle_rpc_supp_cmd(ctx, arg); + } +} + +/** + * optee_handle_rpc() - handle RPC from secure world + * @ctx: context doing the RPC + * @param: value of registers for the RPC + * @call_ctx: call context. Preserved during one OP-TEE invocation + * + * Result of RPC is written back into @param. + */ +void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param, + struct optee_call_ctx *call_ctx) +{ + struct tee_device *teedev = ctx->teedev; + struct optee *optee = tee_get_drvdata(teedev); + struct tee_shm *shm; + phys_addr_t pa; + + switch (OPTEE_SMC_RETURN_GET_RPC_FUNC(param->a0)) { + case OPTEE_SMC_RPC_FUNC_ALLOC: + shm = tee_shm_alloc(ctx, param->a1, TEE_SHM_MAPPED); + if (!IS_ERR(shm) && !tee_shm_get_pa(shm, 0, &pa)) { + reg_pair_from_64(¶m->a1, ¶m->a2, pa); + reg_pair_from_64(¶m->a4, ¶m->a5, + (unsigned long)shm); + } else { + param->a1 = 0; + param->a2 = 0; + param->a4 = 0; + param->a5 = 0; + } + break; + case OPTEE_SMC_RPC_FUNC_FREE: + shm = reg_pair_to_ptr(param->a1, param->a2); + tee_shm_free(shm); + break; + case OPTEE_SMC_RPC_FUNC_FOREIGN_INTR: + /* + * A foreign interrupt was raised while secure world was + * executing, since they are handled in Linux a dummy RPC is + * performed to let Linux take the interrupt through the normal + * vector. + */ + break; + case OPTEE_SMC_RPC_FUNC_CMD: + shm = reg_pair_to_ptr(param->a1, param->a2); + handle_rpc_func_cmd(ctx, optee, shm, call_ctx); + break; + default: + pr_warn("Unknown RPC func 0x%x\n", + (u32)OPTEE_SMC_RETURN_GET_RPC_FUNC(param->a0)); + break; + } + + param->a0 = OPTEE_SMC_CALL_RETURN_FROM_RPC; +} |