diff options
Diffstat (limited to 'drivers/tee/tstee/core.c')
-rw-r--r-- | drivers/tee/tstee/core.c | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/drivers/tee/tstee/core.c b/drivers/tee/tstee/core.c new file mode 100644 index 0000000000..533425e9e9 --- /dev/null +++ b/drivers/tee/tstee/core.c @@ -0,0 +1,480 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023, Arm Limited + */ + +#include <linux/arm_ffa.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/limits.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> +#include <linux/tee_core.h> +#include <linux/types.h> +#include <linux/uuid.h> +#include <linux/xarray.h> +#include "tstee_private.h" + +#define FFA_DIRECT_REQ_ARG_NUM 5 +#define FFA_INVALID_MEM_HANDLE U64_MAX + +static void arg_list_to_ffa_data(const u32 *args, + struct ffa_send_direct_data *data) +{ + data->data0 = args[0]; + data->data1 = args[1]; + data->data2 = args[2]; + data->data3 = args[3]; + data->data4 = args[4]; +} + +static void arg_list_from_ffa_data(const struct ffa_send_direct_data *data, + u32 *args) +{ + args[0] = lower_32_bits(data->data0); + args[1] = lower_32_bits(data->data1); + args[2] = lower_32_bits(data->data2); + args[3] = lower_32_bits(data->data3); + args[4] = lower_32_bits(data->data4); +} + +static void tstee_get_version(struct tee_device *teedev, + struct tee_ioctl_version_data *vers) +{ + struct tstee *tstee = tee_get_drvdata(teedev); + struct tee_ioctl_version_data v = { + .impl_id = TEE_IMPL_ID_TSTEE, + /* FF-A endpoint ID only uses the lower 16 bits */ + .impl_caps = lower_16_bits(tstee->ffa_dev->vm_id), + .gen_caps = 0, + }; + + *vers = v; +} + +static int tstee_open(struct tee_context *ctx) +{ + struct ts_context_data *ctxdata; + + ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL); + if (!ctxdata) + return -ENOMEM; + + xa_init_flags(&ctxdata->sess_list, XA_FLAGS_ALLOC); + + ctx->data = ctxdata; + + return 0; +} + +static void tstee_release(struct tee_context *ctx) +{ + struct ts_context_data *ctxdata = ctx->data; + struct ts_session *sess; + unsigned long idx; + + if (!ctxdata) + return; + + xa_for_each(&ctxdata->sess_list, idx, sess) { + xa_erase(&ctxdata->sess_list, idx); + kfree(sess); + } + + xa_destroy(&ctxdata->sess_list); + + kfree(ctxdata); + ctx->data = NULL; +} + +static int tstee_open_session(struct tee_context *ctx, + struct tee_ioctl_open_session_arg *arg, + struct tee_param *param __always_unused) +{ + struct tstee *tstee = tee_get_drvdata(ctx->teedev); + struct ffa_device *ffa_dev = tstee->ffa_dev; + struct ts_context_data *ctxdata = ctx->data; + struct ffa_send_direct_data ffa_data; + struct ts_session *sess = NULL; + u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {}; + u32 sess_id; + int rc; + + ffa_args[TS_RPC_CTRL_REG] = + TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID, + TS_RPC_OP_SERVICE_INFO); + + memcpy(ffa_args + TS_RPC_SERVICE_INFO_UUID0, arg->uuid, UUID_SIZE); + + arg_list_to_ffa_data(ffa_args, &ffa_data); + rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data); + if (rc) + return rc; + + arg_list_from_ffa_data(&ffa_data, ffa_args); + + if (ffa_args[TS_RPC_SERVICE_INFO_RPC_STATUS] != TS_RPC_OK) + return -ENODEV; + + if (ffa_args[TS_RPC_SERVICE_INFO_IFACE] > U8_MAX) + return -EINVAL; + + sess = kzalloc(sizeof(*sess), GFP_KERNEL); + if (!sess) + return -ENOMEM; + + sess->iface_id = ffa_args[TS_RPC_SERVICE_INFO_IFACE]; + + rc = xa_alloc(&ctxdata->sess_list, &sess_id, sess, xa_limit_32b, + GFP_KERNEL); + if (rc) { + kfree(sess); + return rc; + } + + arg->session = sess_id; + arg->ret = 0; + + return 0; +} + +static int tstee_close_session(struct tee_context *ctx, u32 session) +{ + struct ts_context_data *ctxdata = ctx->data; + struct ts_session *sess; + + /* Calls xa_lock() internally */ + sess = xa_erase(&ctxdata->sess_list, session); + if (!sess) + return -EINVAL; + + kfree(sess); + + return 0; +} + +static int tstee_invoke_func(struct tee_context *ctx, + struct tee_ioctl_invoke_arg *arg, + struct tee_param *param) +{ + struct tstee *tstee = tee_get_drvdata(ctx->teedev); + struct ffa_device *ffa_dev = tstee->ffa_dev; + struct ts_context_data *ctxdata = ctx->data; + struct ffa_send_direct_data ffa_data; + struct tee_shm *shm = NULL; + struct ts_session *sess; + u32 req_len, ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {}; + int shm_id, rc; + u8 iface_id; + u64 handle; + u16 opcode; + + xa_lock(&ctxdata->sess_list); + sess = xa_load(&ctxdata->sess_list, arg->session); + + /* + * Do this while holding the lock to make sure that the session wasn't + * closed meanwhile + */ + if (sess) + iface_id = sess->iface_id; + + xa_unlock(&ctxdata->sess_list); + if (!sess) + return -EINVAL; + + opcode = lower_16_bits(arg->func); + shm_id = lower_32_bits(param[0].u.value.a); + req_len = lower_32_bits(param[0].u.value.b); + + if (shm_id != 0) { + shm = tee_shm_get_from_id(ctx, shm_id); + if (IS_ERR(shm)) + return PTR_ERR(shm); + + if (shm->size < req_len) { + dev_err(&ffa_dev->dev, + "request doesn't fit into shared memory buffer\n"); + rc = -EINVAL; + goto out; + } + + handle = shm->sec_world_id; + } else { + handle = FFA_INVALID_MEM_HANDLE; + } + + ffa_args[TS_RPC_CTRL_REG] = TS_RPC_CTRL_PACK_IFACE_OPCODE(iface_id, + opcode); + ffa_args[TS_RPC_SERVICE_MEM_HANDLE_LSW] = lower_32_bits(handle); + ffa_args[TS_RPC_SERVICE_MEM_HANDLE_MSW] = upper_32_bits(handle); + ffa_args[TS_RPC_SERVICE_REQ_LEN] = req_len; + ffa_args[TS_RPC_SERVICE_CLIENT_ID] = 0; + + arg_list_to_ffa_data(ffa_args, &ffa_data); + rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data); + if (rc) + goto out; + + arg_list_from_ffa_data(&ffa_data, ffa_args); + + if (ffa_args[TS_RPC_SERVICE_RPC_STATUS] != TS_RPC_OK) { + dev_err(&ffa_dev->dev, "invoke_func rpc status: %d\n", + ffa_args[TS_RPC_SERVICE_RPC_STATUS]); + rc = -EINVAL; + goto out; + } + + arg->ret = ffa_args[TS_RPC_SERVICE_STATUS]; + if (shm && shm->size >= ffa_args[TS_RPC_SERVICE_RESP_LEN]) + param[0].u.value.a = ffa_args[TS_RPC_SERVICE_RESP_LEN]; + +out: + if (shm) + tee_shm_put(shm); + + return rc; +} + +static int tstee_shm_register(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages, + unsigned long start __always_unused) +{ + struct tstee *tstee = tee_get_drvdata(ctx->teedev); + struct ffa_device *ffa_dev = tstee->ffa_dev; + struct ffa_mem_region_attributes mem_attr = { + .receiver = tstee->ffa_dev->vm_id, + .attrs = FFA_MEM_RW, + .flag = 0, + }; + struct ffa_mem_ops_args mem_args = { + .attrs = &mem_attr, + .use_txbuf = true, + .nattrs = 1, + .flags = 0, + }; + struct ffa_send_direct_data ffa_data; + struct sg_table sgt; + u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {}; + int rc; + + rc = sg_alloc_table_from_pages(&sgt, pages, num_pages, 0, + num_pages * PAGE_SIZE, GFP_KERNEL); + if (rc) + return rc; + + mem_args.sg = sgt.sgl; + rc = ffa_dev->ops->mem_ops->memory_share(&mem_args); + sg_free_table(&sgt); + if (rc) + return rc; + + shm->sec_world_id = mem_args.g_handle; + + ffa_args[TS_RPC_CTRL_REG] = + TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID, + TS_RPC_OP_RETRIEVE_MEM); + ffa_args[TS_RPC_RETRIEVE_MEM_HANDLE_LSW] = + lower_32_bits(shm->sec_world_id); + ffa_args[TS_RPC_RETRIEVE_MEM_HANDLE_MSW] = + upper_32_bits(shm->sec_world_id); + ffa_args[TS_RPC_RETRIEVE_MEM_TAG_LSW] = 0; + ffa_args[TS_RPC_RETRIEVE_MEM_TAG_MSW] = 0; + + arg_list_to_ffa_data(ffa_args, &ffa_data); + rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data); + if (rc) { + (void)ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id, + 0); + return rc; + } + + arg_list_from_ffa_data(&ffa_data, ffa_args); + + if (ffa_args[TS_RPC_RETRIEVE_MEM_RPC_STATUS] != TS_RPC_OK) { + dev_err(&ffa_dev->dev, "shm_register rpc status: %d\n", + ffa_args[TS_RPC_RETRIEVE_MEM_RPC_STATUS]); + ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id, 0); + return -EINVAL; + } + + return 0; +} + +static int tstee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm) +{ + struct tstee *tstee = tee_get_drvdata(ctx->teedev); + struct ffa_device *ffa_dev = tstee->ffa_dev; + struct ffa_send_direct_data ffa_data; + u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {}; + int rc; + + ffa_args[TS_RPC_CTRL_REG] = + TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID, + TS_RPC_OP_RELINQ_MEM); + ffa_args[TS_RPC_RELINQ_MEM_HANDLE_LSW] = + lower_32_bits(shm->sec_world_id); + ffa_args[TS_RPC_RELINQ_MEM_HANDLE_MSW] = + upper_32_bits(shm->sec_world_id); + + arg_list_to_ffa_data(ffa_args, &ffa_data); + rc = ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data); + if (rc) + return rc; + arg_list_from_ffa_data(&ffa_data, ffa_args); + + if (ffa_args[TS_RPC_RELINQ_MEM_RPC_STATUS] != TS_RPC_OK) { + dev_err(&ffa_dev->dev, "shm_unregister rpc status: %d\n", + ffa_args[TS_RPC_RELINQ_MEM_RPC_STATUS]); + return -EINVAL; + } + + rc = ffa_dev->ops->mem_ops->memory_reclaim(shm->sec_world_id, 0); + + return rc; +} + +static const struct tee_driver_ops tstee_ops = { + .get_version = tstee_get_version, + .open = tstee_open, + .release = tstee_release, + .open_session = tstee_open_session, + .close_session = tstee_close_session, + .invoke_func = tstee_invoke_func, +}; + +static const struct tee_desc tstee_desc = { + .name = "tstee-clnt", + .ops = &tstee_ops, + .owner = THIS_MODULE, +}; + +static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm, + size_t size, size_t align) +{ + return tee_dyn_shm_alloc_helper(shm, size, align, tstee_shm_register); +} + +static void pool_op_free(struct tee_shm_pool *pool, struct tee_shm *shm) +{ + tee_dyn_shm_free_helper(shm, tstee_shm_unregister); +} + +static void pool_op_destroy_pool(struct tee_shm_pool *pool) +{ + kfree(pool); +} + +static const struct tee_shm_pool_ops pool_ops = { + .alloc = pool_op_alloc, + .free = pool_op_free, + .destroy_pool = pool_op_destroy_pool, +}; + +static struct tee_shm_pool *tstee_create_shm_pool(void) +{ + struct tee_shm_pool *pool = kzalloc(sizeof(*pool), GFP_KERNEL); + + if (!pool) + return ERR_PTR(-ENOMEM); + + pool->ops = &pool_ops; + + return pool; +} + +static bool tstee_check_rpc_compatible(struct ffa_device *ffa_dev) +{ + struct ffa_send_direct_data ffa_data; + u32 ffa_args[FFA_DIRECT_REQ_ARG_NUM] = {}; + + ffa_args[TS_RPC_CTRL_REG] = + TS_RPC_CTRL_PACK_IFACE_OPCODE(TS_RPC_MGMT_IFACE_ID, + TS_RPC_OP_GET_VERSION); + + arg_list_to_ffa_data(ffa_args, &ffa_data); + if (ffa_dev->ops->msg_ops->sync_send_receive(ffa_dev, &ffa_data)) + return false; + + arg_list_from_ffa_data(&ffa_data, ffa_args); + + return ffa_args[TS_RPC_GET_VERSION_RESP] == TS_RPC_PROTOCOL_VERSION; +} + +static int tstee_probe(struct ffa_device *ffa_dev) +{ + struct tstee *tstee; + int rc; + + ffa_dev->ops->msg_ops->mode_32bit_set(ffa_dev); + + if (!tstee_check_rpc_compatible(ffa_dev)) + return -EINVAL; + + tstee = kzalloc(sizeof(*tstee), GFP_KERNEL); + if (!tstee) + return -ENOMEM; + + tstee->ffa_dev = ffa_dev; + + tstee->pool = tstee_create_shm_pool(); + if (IS_ERR(tstee->pool)) { + rc = PTR_ERR(tstee->pool); + tstee->pool = NULL; + goto err_free_tstee; + } + + tstee->teedev = tee_device_alloc(&tstee_desc, NULL, tstee->pool, tstee); + if (IS_ERR(tstee->teedev)) { + rc = PTR_ERR(tstee->teedev); + tstee->teedev = NULL; + goto err_free_pool; + } + + rc = tee_device_register(tstee->teedev); + if (rc) + goto err_unreg_teedev; + + ffa_dev_set_drvdata(ffa_dev, tstee); + + return 0; + +err_unreg_teedev: + tee_device_unregister(tstee->teedev); +err_free_pool: + tee_shm_pool_free(tstee->pool); +err_free_tstee: + kfree(tstee); + return rc; +} + +static void tstee_remove(struct ffa_device *ffa_dev) +{ + struct tstee *tstee = ffa_dev->dev.driver_data; + + tee_device_unregister(tstee->teedev); + tee_shm_pool_free(tstee->pool); + kfree(tstee); +} + +static const struct ffa_device_id tstee_device_ids[] = { + /* TS RPC protocol UUID: bdcd76d7-825e-4751-963b-86d4f84943ac */ + { TS_RPC_UUID }, + {} +}; + +static struct ffa_driver tstee_driver = { + .name = "arm_tstee", + .probe = tstee_probe, + .remove = tstee_remove, + .id_table = tstee_device_ids, +}; + +module_ffa_driver(tstee_driver); + +MODULE_AUTHOR("Balint Dobszay <balint.dobszay@arm.com>"); +MODULE_DESCRIPTION("Arm Trusted Services TEE driver"); +MODULE_LICENSE("GPL"); |