diff options
Diffstat (limited to 'drivers/tee/optee/smc_abi.c')
| -rw-r--r-- | drivers/tee/optee/smc_abi.c | 1362 |
1 files changed, 1362 insertions, 0 deletions
diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c new file mode 100644 index 000000000000..6196d7c3888f --- /dev/null +++ b/drivers/tee/optee/smc_abi.c @@ -0,0 +1,1362 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2015-2021, Linaro Limited + * Copyright (c) 2016, EPAM Systems + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/arm-smccc.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/tee_drv.h> +#include <linux/types.h> +#include <linux/workqueue.h> +#include "optee_private.h" +#include "optee_smc.h" +#include "optee_rpc_cmd.h" +#define CREATE_TRACE_POINTS +#include "optee_trace.h" + +/* + * This file implement the SMC ABI used when communicating with secure world + * OP-TEE OS via raw SMCs. + * This file is divided into the following sections: + * 1. Convert between struct tee_param and struct optee_msg_param + * 2. Low level support functions to register shared memory in secure world + * 3. Dynamic shared memory pool based on alloc_pages() + * 4. Do a normal scheduled call into secure world + * 5. Driver initialization. + */ + +#define OPTEE_SHM_NUM_PRIV_PAGES CONFIG_OPTEE_SHM_NUM_PRIV_PAGES + +/* + * 1. Convert between struct tee_param and struct optee_msg_param + * + * optee_from_msg_param() and optee_to_msg_param() are the main + * functions. + */ + +static int from_msg_param_tmp_mem(struct tee_param *p, u32 attr, + const struct optee_msg_param *mp) +{ + struct tee_shm *shm; + phys_addr_t pa; + int rc; + + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT + + attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT; + p->u.memref.size = mp->u.tmem.size; + shm = (struct tee_shm *)(unsigned long)mp->u.tmem.shm_ref; + if (!shm) { + p->u.memref.shm_offs = 0; + p->u.memref.shm = NULL; + return 0; + } + + rc = tee_shm_get_pa(shm, 0, &pa); + if (rc) + return rc; + + p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa; + p->u.memref.shm = shm; + + /* Check that the memref is covered by the shm object */ + if (p->u.memref.size) { + size_t o = p->u.memref.shm_offs + + p->u.memref.size - 1; + + rc = tee_shm_get_pa(shm, o, NULL); + if (rc) + return rc; + } + + return 0; +} + +static void from_msg_param_reg_mem(struct tee_param *p, u32 attr, + const struct optee_msg_param *mp) +{ + struct tee_shm *shm; + + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT + + attr - OPTEE_MSG_ATTR_TYPE_RMEM_INPUT; + p->u.memref.size = mp->u.rmem.size; + shm = (struct tee_shm *)(unsigned long)mp->u.rmem.shm_ref; + + if (shm) { + p->u.memref.shm_offs = mp->u.rmem.offs; + p->u.memref.shm = shm; + } else { + p->u.memref.shm_offs = 0; + p->u.memref.shm = NULL; + } +} + +/** + * optee_from_msg_param() - convert from OPTEE_MSG parameters to + * struct tee_param + * @optee: main service struct + * @params: subsystem internal parameter representation + * @num_params: number of elements in the parameter arrays + * @msg_params: OPTEE_MSG parameters + * Returns 0 on success or <0 on failure + */ +static int optee_from_msg_param(struct optee *optee, struct tee_param *params, + size_t num_params, + const struct optee_msg_param *msg_params) +{ + int rc; + size_t n; + + for (n = 0; n < num_params; n++) { + struct tee_param *p = params + n; + const struct optee_msg_param *mp = msg_params + n; + u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK; + + switch (attr) { + case OPTEE_MSG_ATTR_TYPE_NONE: + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + memset(&p->u, 0, sizeof(p->u)); + break; + case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT: + case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT: + case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT: + optee_from_msg_param_value(p, attr, mp); + break; + case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT: + case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT: + case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT: + rc = from_msg_param_tmp_mem(p, attr, mp); + if (rc) + return rc; + break; + case OPTEE_MSG_ATTR_TYPE_RMEM_INPUT: + case OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT: + case OPTEE_MSG_ATTR_TYPE_RMEM_INOUT: + from_msg_param_reg_mem(p, attr, mp); + break; + + default: + return -EINVAL; + } + } + return 0; +} + +static int to_msg_param_tmp_mem(struct optee_msg_param *mp, + const struct tee_param *p) +{ + int rc; + phys_addr_t pa; + + mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT + p->attr - + TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + + mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm; + mp->u.tmem.size = p->u.memref.size; + + if (!p->u.memref.shm) { + mp->u.tmem.buf_ptr = 0; + return 0; + } + + rc = tee_shm_get_pa(p->u.memref.shm, p->u.memref.shm_offs, &pa); + if (rc) + return rc; + + mp->u.tmem.buf_ptr = pa; + mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED << + OPTEE_MSG_ATTR_CACHE_SHIFT; + + return 0; +} + +static int to_msg_param_reg_mem(struct optee_msg_param *mp, + const struct tee_param *p) +{ + mp->attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT + p->attr - + TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + + mp->u.rmem.shm_ref = (unsigned long)p->u.memref.shm; + mp->u.rmem.size = p->u.memref.size; + mp->u.rmem.offs = p->u.memref.shm_offs; + return 0; +} + +/** + * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters + * @optee: main service struct + * @msg_params: OPTEE_MSG parameters + * @num_params: number of elements in the parameter arrays + * @params: subsystem itnernal parameter representation + * Returns 0 on success or <0 on failure + */ +static int optee_to_msg_param(struct optee *optee, + struct optee_msg_param *msg_params, + size_t num_params, const struct tee_param *params) +{ + int rc; + size_t n; + + for (n = 0; n < num_params; n++) { + const struct tee_param *p = params + n; + struct optee_msg_param *mp = msg_params + n; + + switch (p->attr) { + case TEE_IOCTL_PARAM_ATTR_TYPE_NONE: + mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + memset(&mp->u, 0, sizeof(mp->u)); + break; + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT: + optee_to_msg_param_value(mp, p); + break; + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT: + if (tee_shm_is_registered(p->u.memref.shm)) + rc = to_msg_param_reg_mem(mp, p); + else + rc = to_msg_param_tmp_mem(mp, p); + if (rc) + return rc; + break; + default: + return -EINVAL; + } + } + return 0; +} + +/* + * 2. Low level support functions to register shared memory in secure world + * + * Functions to enable/disable shared memory caching in secure world, that + * is, lazy freeing of previously allocated shared memory. Freeing is + * performed when a request has been compled. + * + * Functions to register and unregister shared memory both for normal + * clients and for tee-supplicant. + */ + +/** + * optee_enable_shm_cache() - Enables caching of some shared memory allocation + * in OP-TEE + * @optee: main service struct + */ +static void optee_enable_shm_cache(struct optee *optee) +{ + struct optee_call_waiter w; + + /* We need to retry until secure world isn't busy. */ + optee_cq_wait_init(&optee->call_queue, &w); + while (true) { + struct arm_smccc_res res; + + optee->smc.invoke_fn(OPTEE_SMC_ENABLE_SHM_CACHE, + 0, 0, 0, 0, 0, 0, 0, &res); + if (res.a0 == OPTEE_SMC_RETURN_OK) + break; + optee_cq_wait_for_completion(&optee->call_queue, &w); + } + optee_cq_wait_final(&optee->call_queue, &w); +} + +/** + * __optee_disable_shm_cache() - Disables caching of some shared memory + * allocation in OP-TEE + * @optee: main service struct + * @is_mapped: true if the cached shared memory addresses were mapped by this + * kernel, are safe to dereference, and should be freed + */ +static void __optee_disable_shm_cache(struct optee *optee, bool is_mapped) +{ + struct optee_call_waiter w; + + /* We need to retry until secure world isn't busy. */ + optee_cq_wait_init(&optee->call_queue, &w); + while (true) { + union { + struct arm_smccc_res smccc; + struct optee_smc_disable_shm_cache_result result; + } res; + + optee->smc.invoke_fn(OPTEE_SMC_DISABLE_SHM_CACHE, + 0, 0, 0, 0, 0, 0, 0, &res.smccc); + if (res.result.status == OPTEE_SMC_RETURN_ENOTAVAIL) + break; /* All shm's freed */ + if (res.result.status == OPTEE_SMC_RETURN_OK) { + struct tee_shm *shm; + + /* + * Shared memory references that were not mapped by + * this kernel must be ignored to prevent a crash. + */ + if (!is_mapped) + continue; + + shm = reg_pair_to_ptr(res.result.shm_upper32, + res.result.shm_lower32); + tee_shm_free(shm); + } else { + optee_cq_wait_for_completion(&optee->call_queue, &w); + } + } + optee_cq_wait_final(&optee->call_queue, &w); +} + +/** + * optee_disable_shm_cache() - Disables caching of mapped shared memory + * allocations in OP-TEE + * @optee: main service struct + */ +static void optee_disable_shm_cache(struct optee *optee) +{ + return __optee_disable_shm_cache(optee, true); +} + +/** + * optee_disable_unmapped_shm_cache() - Disables caching of shared memory + * allocations in OP-TEE which are not + * currently mapped + * @optee: main service struct + */ +static void optee_disable_unmapped_shm_cache(struct optee *optee) +{ + return __optee_disable_shm_cache(optee, false); +} + +#define PAGELIST_ENTRIES_PER_PAGE \ + ((OPTEE_MSG_NONCONTIG_PAGE_SIZE / sizeof(u64)) - 1) + +/* + * The final entry in each pagelist page is a pointer to the next + * pagelist page. + */ +static size_t get_pages_list_size(size_t num_entries) +{ + int pages = DIV_ROUND_UP(num_entries, PAGELIST_ENTRIES_PER_PAGE); + + return pages * OPTEE_MSG_NONCONTIG_PAGE_SIZE; +} + +static u64 *optee_allocate_pages_list(size_t num_entries) +{ + return alloc_pages_exact(get_pages_list_size(num_entries), GFP_KERNEL); +} + +static void optee_free_pages_list(void *list, size_t num_entries) +{ + free_pages_exact(list, get_pages_list_size(num_entries)); +} + +/** + * optee_fill_pages_list() - write list of user pages to given shared + * buffer. + * + * @dst: page-aligned buffer where list of pages will be stored + * @pages: array of pages that represents shared buffer + * @num_pages: number of entries in @pages + * @page_offset: offset of user buffer from page start + * + * @dst should be big enough to hold list of user page addresses and + * links to the next pages of buffer + */ +static void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages, + size_t page_offset) +{ + int n = 0; + phys_addr_t optee_page; + /* + * Refer to OPTEE_MSG_ATTR_NONCONTIG description in optee_msg.h + * for details. + */ + struct { + u64 pages_list[PAGELIST_ENTRIES_PER_PAGE]; + u64 next_page_data; + } *pages_data; + + /* + * Currently OP-TEE uses 4k page size and it does not looks + * like this will change in the future. On other hand, there are + * no know ARM architectures with page size < 4k. + * Thus the next built assert looks redundant. But the following + * code heavily relies on this assumption, so it is better be + * safe than sorry. + */ + BUILD_BUG_ON(PAGE_SIZE < OPTEE_MSG_NONCONTIG_PAGE_SIZE); + + pages_data = (void *)dst; + /* + * If linux page is bigger than 4k, and user buffer offset is + * larger than 4k/8k/12k/etc this will skip first 4k pages, + * because they bear no value data for OP-TEE. + */ + optee_page = page_to_phys(*pages) + + round_down(page_offset, OPTEE_MSG_NONCONTIG_PAGE_SIZE); + + while (true) { + pages_data->pages_list[n++] = optee_page; + + if (n == PAGELIST_ENTRIES_PER_PAGE) { + pages_data->next_page_data = + virt_to_phys(pages_data + 1); + pages_data++; + n = 0; + } + + optee_page += OPTEE_MSG_NONCONTIG_PAGE_SIZE; + if (!(optee_page & ~PAGE_MASK)) { + if (!--num_pages) + break; + pages++; + optee_page = page_to_phys(*pages); + } + } +} + +static int optee_shm_register(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages, + unsigned long start) +{ + struct optee *optee = tee_get_drvdata(ctx->teedev); + struct optee_msg_arg *msg_arg; + struct tee_shm *shm_arg; + u64 *pages_list; + int rc; + + if (!num_pages) + return -EINVAL; + + rc = optee_check_mem_type(start, num_pages); + if (rc) + return rc; + + pages_list = optee_allocate_pages_list(num_pages); + if (!pages_list) + return -ENOMEM; + + shm_arg = optee_get_msg_arg(ctx, 1, &msg_arg); + if (IS_ERR(shm_arg)) { + rc = PTR_ERR(shm_arg); + goto out; + } + + optee_fill_pages_list(pages_list, pages, num_pages, + tee_shm_get_page_offset(shm)); + + msg_arg->cmd = OPTEE_MSG_CMD_REGISTER_SHM; + msg_arg->params->attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT | + OPTEE_MSG_ATTR_NONCONTIG; + msg_arg->params->u.tmem.shm_ref = (unsigned long)shm; + msg_arg->params->u.tmem.size = tee_shm_get_size(shm); + /* + * In the least bits of msg_arg->params->u.tmem.buf_ptr we + * store buffer offset from 4k page, as described in OP-TEE ABI. + */ + msg_arg->params->u.tmem.buf_ptr = virt_to_phys(pages_list) | + (tee_shm_get_page_offset(shm) & (OPTEE_MSG_NONCONTIG_PAGE_SIZE - 1)); + + if (optee->ops->do_call_with_arg(ctx, shm_arg) || + msg_arg->ret != TEEC_SUCCESS) + rc = -EINVAL; + + tee_shm_free(shm_arg); +out: + optee_free_pages_list(pages_list, num_pages); + return rc; +} + +static int optee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm) +{ + struct optee *optee = tee_get_drvdata(ctx->teedev); + struct optee_msg_arg *msg_arg; + struct tee_shm *shm_arg; + int rc = 0; + + shm_arg = optee_get_msg_arg(ctx, 1, &msg_arg); + if (IS_ERR(shm_arg)) + return PTR_ERR(shm_arg); + + msg_arg->cmd = OPTEE_MSG_CMD_UNREGISTER_SHM; + + msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT; + msg_arg->params[0].u.rmem.shm_ref = (unsigned long)shm; + + if (optee->ops->do_call_with_arg(ctx, shm_arg) || + msg_arg->ret != TEEC_SUCCESS) + rc = -EINVAL; + tee_shm_free(shm_arg); + return rc; +} + +static int optee_shm_register_supp(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages, + unsigned long start) +{ + /* + * We don't want to register supplicant memory in OP-TEE. + * Instead information about it will be passed in RPC code. + */ + return optee_check_mem_type(start, num_pages); +} + +static int optee_shm_unregister_supp(struct tee_context *ctx, + struct tee_shm *shm) +{ + return 0; +} + +/* + * 3. Dynamic shared memory pool based on alloc_pages() + * + * Implements an OP-TEE specific shared memory pool which is used + * when dynamic shared memory is supported by secure world. + * + * The main function is optee_shm_pool_alloc_pages(). + */ + +static int pool_op_alloc(struct tee_shm_pool_mgr *poolm, + struct tee_shm *shm, size_t size) +{ + /* + * Shared memory private to the OP-TEE driver doesn't need + * to be registered with OP-TEE. + */ + if (shm->flags & TEE_SHM_PRIV) + return optee_pool_op_alloc_helper(poolm, shm, size, NULL); + + return optee_pool_op_alloc_helper(poolm, shm, size, optee_shm_register); +} + +static void pool_op_free(struct tee_shm_pool_mgr *poolm, + struct tee_shm *shm) +{ + if (!(shm->flags & TEE_SHM_PRIV)) + optee_shm_unregister(shm->ctx, shm); + + free_pages((unsigned long)shm->kaddr, get_order(shm->size)); + shm->kaddr = NULL; +} + +static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm) +{ + kfree(poolm); +} + +static const struct tee_shm_pool_mgr_ops pool_ops = { + .alloc = pool_op_alloc, + .free = pool_op_free, + .destroy_poolmgr = pool_op_destroy_poolmgr, +}; + +/** + * optee_shm_pool_alloc_pages() - create page-based allocator pool + * + * This pool is used when OP-TEE supports dymanic SHM. In this case + * command buffers and such are allocated from kernel's own memory. + */ +static struct tee_shm_pool_mgr *optee_shm_pool_alloc_pages(void) +{ + struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL); + + if (!mgr) + return ERR_PTR(-ENOMEM); + + mgr->ops = &pool_ops; + + return mgr; +} + +/* + * 4. Do a normal scheduled call into secure world + * + * The function optee_smc_do_call_with_arg() performs a normal scheduled + * call into secure world. During this call may normal world request help + * from normal world using RPCs, Remote Procedure Calls. This includes + * delivery of non-secure interrupts to for instance allow rescheduling of + * the current task. + */ + +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_RPC_SHM_TYPE_APPL: + optee_rpc_cmd_free_suppl(ctx, shm); + break; + case OPTEE_RPC_SHM_TYPE_KERNEL: + tee_shm_free(shm); + break; + default: + arg->ret = TEEC_ERROR_BAD_PARAMETERS; + } + arg->ret = TEEC_SUCCESS; +} + +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_RPC_SHM_TYPE_APPL: + shm = optee_rpc_cmd_alloc_suppl(ctx, sz); + break; + case OPTEE_RPC_SHM_TYPE_KERNEL: + shm = tee_shm_alloc(ctx, sz, TEE_SHM_MAPPED | TEE_SHM_PRIV); + 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 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; + } +} + +static 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_RPC_CMD_SHM_ALLOC: + free_pages_list(call_ctx); + handle_rpc_func_cmd_shm_alloc(ctx, arg, call_ctx); + break; + case OPTEE_RPC_CMD_SHM_FREE: + handle_rpc_func_cmd_shm_free(ctx, arg); + break; + default: + optee_rpc_cmd(ctx, optee, 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. + */ +static 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 | TEE_SHM_PRIV); + 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; +} + +/** + * optee_smc_do_call_with_arg() - Do an SMC to OP-TEE in secure world + * @ctx: calling context + * @arg: shared memory holding the message to pass to secure world + * + * Does and SMC to OP-TEE in secure world and handles eventual resulting + * Remote Procedure Calls (RPC) from OP-TEE. + * + * Returns return code from secure world, 0 is OK + */ +static int optee_smc_do_call_with_arg(struct tee_context *ctx, + struct tee_shm *arg) +{ + struct optee *optee = tee_get_drvdata(ctx->teedev); + struct optee_call_waiter w; + struct optee_rpc_param param = { }; + struct optee_call_ctx call_ctx = { }; + phys_addr_t parg; + int rc; + + rc = tee_shm_get_pa(arg, 0, &parg); + if (rc) + return rc; + + param.a0 = OPTEE_SMC_CALL_WITH_ARG; + reg_pair_from_64(¶m.a1, ¶m.a2, parg); + /* Initialize waiter */ + optee_cq_wait_init(&optee->call_queue, &w); + while (true) { + struct arm_smccc_res res; + + trace_optee_invoke_fn_begin(¶m); + optee->smc.invoke_fn(param.a0, param.a1, param.a2, param.a3, + param.a4, param.a5, param.a6, param.a7, + &res); + trace_optee_invoke_fn_end(¶m, &res); + + if (res.a0 == OPTEE_SMC_RETURN_ETHREAD_LIMIT) { + /* + * Out of threads in secure world, wait for a thread + * become available. + */ + optee_cq_wait_for_completion(&optee->call_queue, &w); + } else if (OPTEE_SMC_RETURN_IS_RPC(res.a0)) { + cond_resched(); + param.a0 = res.a0; + param.a1 = res.a1; + param.a2 = res.a2; + param.a3 = res.a3; + optee_handle_rpc(ctx, ¶m, &call_ctx); + } else { + rc = res.a0; + break; + } + } + + optee_rpc_finalize_call(&call_ctx); + /* + * We're done with our thread in secure world, if there's any + * thread waiters wake up one. + */ + optee_cq_wait_final(&optee->call_queue, &w); + + return rc; +} + +/* + * 5. Driver initialization + * + * During driver inititialization is secure world probed to find out which + * features it supports so the driver can be initialized with a matching + * configuration. This involves for instance support for dynamic shared + * memory instead of a static memory carvout. + */ + +static void optee_get_version(struct tee_device *teedev, + struct tee_ioctl_version_data *vers) +{ + struct tee_ioctl_version_data v = { + .impl_id = TEE_IMPL_ID_OPTEE, + .impl_caps = TEE_OPTEE_CAP_TZ, + .gen_caps = TEE_GEN_CAP_GP, + }; + struct optee *optee = tee_get_drvdata(teedev); + + if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) + v.gen_caps |= TEE_GEN_CAP_REG_MEM; + if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_MEMREF_NULL) + v.gen_caps |= TEE_GEN_CAP_MEMREF_NULL; + *vers = v; +} + +static int optee_smc_open(struct tee_context *ctx) +{ + struct optee *optee = tee_get_drvdata(ctx->teedev); + u32 sec_caps = optee->smc.sec_caps; + + return optee_open(ctx, sec_caps & OPTEE_SMC_SEC_CAP_MEMREF_NULL); +} + +static const struct tee_driver_ops optee_clnt_ops = { + .get_version = optee_get_version, + .open = optee_smc_open, + .release = optee_release, + .open_session = optee_open_session, + .close_session = optee_close_session, + .invoke_func = optee_invoke_func, + .cancel_req = optee_cancel_req, + .shm_register = optee_shm_register, + .shm_unregister = optee_shm_unregister, +}; + +static const struct tee_desc optee_clnt_desc = { + .name = DRIVER_NAME "-clnt", + .ops = &optee_clnt_ops, + .owner = THIS_MODULE, +}; + +static const struct tee_driver_ops optee_supp_ops = { + .get_version = optee_get_version, + .open = optee_smc_open, + .release = optee_release_supp, + .supp_recv = optee_supp_recv, + .supp_send = optee_supp_send, + .shm_register = optee_shm_register_supp, + .shm_unregister = optee_shm_unregister_supp, +}; + +static const struct tee_desc optee_supp_desc = { + .name = DRIVER_NAME "-supp", + .ops = &optee_supp_ops, + .owner = THIS_MODULE, + .flags = TEE_DESC_PRIVILEGED, +}; + +static const struct optee_ops optee_ops = { + .do_call_with_arg = optee_smc_do_call_with_arg, + .to_msg_param = optee_to_msg_param, + .from_msg_param = optee_from_msg_param, +}; + +static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn) +{ + struct arm_smccc_res res; + + invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res); + + if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 && + res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3) + return true; + return false; +} + +static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_call_get_os_revision_result result; + } res = { + .result = { + .build_id = 0 + } + }; + + invoke_fn(OPTEE_SMC_CALL_GET_OS_REVISION, 0, 0, 0, 0, 0, 0, 0, + &res.smccc); + + if (res.result.build_id) + pr_info("revision %lu.%lu (%08lx)", res.result.major, + res.result.minor, res.result.build_id); + else + pr_info("revision %lu.%lu", res.result.major, res.result.minor); +} + +static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_calls_revision_result result; + } res; + + invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc); + + if (res.result.major == OPTEE_MSG_REVISION_MAJOR && + (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR) + return true; + return false; +} + +static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn, + u32 *sec_caps) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_exchange_capabilities_result result; + } res; + u32 a1 = 0; + + /* + * TODO This isn't enough to tell if it's UP system (from kernel + * point of view) or not, is_smp() returns the information + * needed, but can't be called directly from here. + */ + if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1) + a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR; + + invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0, + &res.smccc); + + if (res.result.status != OPTEE_SMC_RETURN_OK) + return false; + + *sec_caps = res.result.capabilities; + return true; +} + +static struct tee_shm_pool *optee_config_dyn_shm(void) +{ + struct tee_shm_pool_mgr *priv_mgr; + struct tee_shm_pool_mgr *dmabuf_mgr; + void *rc; + + rc = optee_shm_pool_alloc_pages(); + if (IS_ERR(rc)) + return rc; + priv_mgr = rc; + + rc = optee_shm_pool_alloc_pages(); + if (IS_ERR(rc)) { + tee_shm_pool_mgr_destroy(priv_mgr); + return rc; + } + dmabuf_mgr = rc; + + rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr); + if (IS_ERR(rc)) { + tee_shm_pool_mgr_destroy(priv_mgr); + tee_shm_pool_mgr_destroy(dmabuf_mgr); + } + + return rc; +} + +static struct tee_shm_pool * +optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_get_shm_config_result result; + } res; + unsigned long vaddr; + phys_addr_t paddr; + size_t size; + phys_addr_t begin; + phys_addr_t end; + void *va; + struct tee_shm_pool_mgr *priv_mgr; + struct tee_shm_pool_mgr *dmabuf_mgr; + void *rc; + const int sz = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE; + + invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc); + if (res.result.status != OPTEE_SMC_RETURN_OK) { + pr_err("static shm service not available\n"); + return ERR_PTR(-ENOENT); + } + + if (res.result.settings != OPTEE_SMC_SHM_CACHED) { + pr_err("only normal cached shared memory supported\n"); + return ERR_PTR(-EINVAL); + } + + begin = roundup(res.result.start, PAGE_SIZE); + end = rounddown(res.result.start + res.result.size, PAGE_SIZE); + paddr = begin; + size = end - begin; + + if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) { + pr_err("too small shared memory area\n"); + return ERR_PTR(-EINVAL); + } + + va = memremap(paddr, size, MEMREMAP_WB); + if (!va) { + pr_err("shared memory ioremap failed\n"); + return ERR_PTR(-EINVAL); + } + vaddr = (unsigned long)va; + + rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, sz, + 3 /* 8 bytes aligned */); + if (IS_ERR(rc)) + goto err_memunmap; + priv_mgr = rc; + + vaddr += sz; + paddr += sz; + size -= sz; + + rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, size, PAGE_SHIFT); + if (IS_ERR(rc)) + goto err_free_priv_mgr; + dmabuf_mgr = rc; + + rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr); + if (IS_ERR(rc)) + goto err_free_dmabuf_mgr; + + *memremaped_shm = va; + + return rc; + +err_free_dmabuf_mgr: + tee_shm_pool_mgr_destroy(dmabuf_mgr); +err_free_priv_mgr: + tee_shm_pool_mgr_destroy(priv_mgr); +err_memunmap: + memunmap(va); + return rc; +} + +/* Simple wrapper functions to be able to use a function pointer */ +static void optee_smccc_smc(unsigned long a0, unsigned long a1, + unsigned long a2, unsigned long a3, + unsigned long a4, unsigned long a5, + unsigned long a6, unsigned long a7, + struct arm_smccc_res *res) +{ + arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res); +} + +static void optee_smccc_hvc(unsigned long a0, unsigned long a1, + unsigned long a2, unsigned long a3, + unsigned long a4, unsigned long a5, + unsigned long a6, unsigned long a7, + struct arm_smccc_res *res) +{ + arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res); +} + +static optee_invoke_fn *get_invoke_func(struct device *dev) +{ + const char *method; + + pr_info("probing for conduit method.\n"); + + if (device_property_read_string(dev, "method", &method)) { + pr_warn("missing \"method\" property\n"); + return ERR_PTR(-ENXIO); + } + + if (!strcmp("hvc", method)) + return optee_smccc_hvc; + else if (!strcmp("smc", method)) + return optee_smccc_smc; + + pr_warn("invalid \"method\" property: %s\n", method); + return ERR_PTR(-EINVAL); +} + +/* optee_remove - Device Removal Routine + * @pdev: platform device information struct + * + * optee_remove is called by platform subsystem to alert the driver + * that it should release the device + */ +static int optee_smc_remove(struct platform_device *pdev) +{ + struct optee *optee = platform_get_drvdata(pdev); + + /* + * Ask OP-TEE to free all cached shared memory objects to decrease + * reference counters and also avoid wild pointers in secure world + * into the old shared memory range. + */ + optee_disable_shm_cache(optee); + + optee_remove_common(optee); + + if (optee->smc.memremaped_shm) + memunmap(optee->smc.memremaped_shm); + + kfree(optee); + + return 0; +} + +/* optee_shutdown - Device Removal Routine + * @pdev: platform device information struct + * + * platform_shutdown is called by the platform subsystem to alert + * the driver that a shutdown, reboot, or kexec is happening and + * device must be disabled. + */ +static void optee_shutdown(struct platform_device *pdev) +{ + optee_disable_shm_cache(platform_get_drvdata(pdev)); +} + +static int optee_probe(struct platform_device *pdev) +{ + optee_invoke_fn *invoke_fn; + struct tee_shm_pool *pool = ERR_PTR(-EINVAL); + struct optee *optee = NULL; + void *memremaped_shm = NULL; + struct tee_device *teedev; + u32 sec_caps; + int rc; + + invoke_fn = get_invoke_func(&pdev->dev); + if (IS_ERR(invoke_fn)) + return PTR_ERR(invoke_fn); + + if (!optee_msg_api_uid_is_optee_api(invoke_fn)) { + pr_warn("api uid mismatch\n"); + return -EINVAL; + } + + optee_msg_get_os_revision(invoke_fn); + + if (!optee_msg_api_revision_is_compatible(invoke_fn)) { + pr_warn("api revision mismatch\n"); + return -EINVAL; + } + + if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) { + pr_warn("capabilities mismatch\n"); + return -EINVAL; + } + + /* + * Try to use dynamic shared memory if possible + */ + if (sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) + pool = optee_config_dyn_shm(); + + /* + * If dynamic shared memory is not available or failed - try static one + */ + if (IS_ERR(pool) && (sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM)) + pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm); + + if (IS_ERR(pool)) + return PTR_ERR(pool); + + optee = kzalloc(sizeof(*optee), GFP_KERNEL); + if (!optee) { + rc = -ENOMEM; + goto err; + } + + optee->ops = &optee_ops; + optee->smc.invoke_fn = invoke_fn; + optee->smc.sec_caps = sec_caps; + + teedev = tee_device_alloc(&optee_clnt_desc, NULL, pool, optee); + if (IS_ERR(teedev)) { + rc = PTR_ERR(teedev); + goto err; + } + optee->teedev = teedev; + + teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee); + if (IS_ERR(teedev)) { + rc = PTR_ERR(teedev); + goto err; + } + optee->supp_teedev = teedev; + + rc = tee_device_register(optee->teedev); + if (rc) + goto err; + + rc = tee_device_register(optee->supp_teedev); + if (rc) + goto err; + + mutex_init(&optee->call_queue.mutex); + INIT_LIST_HEAD(&optee->call_queue.waiters); + optee_wait_queue_init(&optee->wait_queue); + optee_supp_init(&optee->supp); + optee->smc.memremaped_shm = memremaped_shm; + optee->pool = pool; + + /* + * Ensure that there are no pre-existing shm objects before enabling + * the shm cache so that there's no chance of receiving an invalid + * address during shutdown. This could occur, for example, if we're + * kexec booting from an older kernel that did not properly cleanup the + * shm cache. + */ + optee_disable_unmapped_shm_cache(optee); + + optee_enable_shm_cache(optee); + + if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) + pr_info("dynamic shared memory is enabled\n"); + + platform_set_drvdata(pdev, optee); + + rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES); + if (rc) { + optee_smc_remove(pdev); + return rc; + } + + pr_info("initialized driver\n"); + return 0; +err: + if (optee) { + /* + * tee_device_unregister() is safe to call even if the + * devices hasn't been registered with + * tee_device_register() yet. + */ + tee_device_unregister(optee->supp_teedev); + tee_device_unregister(optee->teedev); + kfree(optee); + } + if (pool) + tee_shm_pool_free(pool); + if (memremaped_shm) + memunmap(memremaped_shm); + return rc; +} + +static const struct of_device_id optee_dt_match[] = { + { .compatible = "linaro,optee-tz" }, + {}, +}; +MODULE_DEVICE_TABLE(of, optee_dt_match); + +static struct platform_driver optee_driver = { + .probe = optee_probe, + .remove = optee_smc_remove, + .shutdown = optee_shutdown, + .driver = { + .name = "optee", + .of_match_table = optee_dt_match, + }, +}; + +int optee_smc_abi_register(void) +{ + return platform_driver_register(&optee_driver); +} + +void optee_smc_abi_unregister(void) +{ + platform_driver_unregister(&optee_driver); +} |