Add support in the OP-TEE backend driver dynamic protected memory allocation with FF-A.
The protected memory pools for dynamically allocated protected memory are instantiated when requested by user-space. This instantiation can fail if OP-TEE doesn't support the requested use-case of protected memory.
Restricted memory pools based on a static carveout or dynamic allocation can coexist for different use-cases. We use only dynamic allocation with FF-A.
Signed-off-by: Jens Wiklander jens.wiklander@linaro.org --- drivers/tee/optee/Makefile | 1 + drivers/tee/optee/ffa_abi.c | 147 ++++++++++++- drivers/tee/optee/optee_private.h | 13 +- drivers/tee/optee/protmem.c | 330 ++++++++++++++++++++++++++++++ 4 files changed, 488 insertions(+), 3 deletions(-) create mode 100644 drivers/tee/optee/protmem.c
diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile index a6eff388d300..ad7049c1c107 100644 --- a/drivers/tee/optee/Makefile +++ b/drivers/tee/optee/Makefile @@ -4,6 +4,7 @@ optee-objs += core.o optee-objs += call.o optee-objs += notif.o optee-objs += rpc.o +optee-objs += protmem.o optee-objs += supp.o optee-objs += device.o optee-objs += smc_abi.o diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c index e4b08cd195f3..e1f02fc42c2f 100644 --- a/drivers/tee/optee/ffa_abi.c +++ b/drivers/tee/optee/ffa_abi.c @@ -672,6 +672,124 @@ static int optee_ffa_do_call_with_arg(struct tee_context *ctx, return optee_ffa_yielding_call(ctx, &data, rpc_arg, system_thread); }
+static int do_call_lend_protmem(struct optee *optee, u64 cookie, u32 use_case) +{ + struct optee_shm_arg_entry *entry; + struct optee_msg_arg *msg_arg; + struct tee_shm *shm; + u_int offs; + int rc; + + msg_arg = optee_get_msg_arg(optee->ctx, 1, &entry, &shm, &offs); + if (IS_ERR(msg_arg)) + return PTR_ERR(msg_arg); + + msg_arg->cmd = OPTEE_MSG_CMD_ASSIGN_PROTMEM; + msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT; + msg_arg->params[0].u.value.a = cookie; + msg_arg->params[0].u.value.b = use_case; + + rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false); + if (rc) + goto out; + if (msg_arg->ret != TEEC_SUCCESS) { + rc = -EINVAL; + goto out; + } + +out: + optee_free_msg_arg(optee->ctx, entry, offs); + return rc; +} + +static int optee_ffa_lend_protmem(struct optee *optee, struct tee_shm *protmem, + u16 *end_points, unsigned int ep_count, + u32 use_case) +{ + struct ffa_device *ffa_dev = optee->ffa.ffa_dev; + const struct ffa_mem_ops *mem_ops = ffa_dev->ops->mem_ops; + const struct ffa_msg_ops *msg_ops = ffa_dev->ops->msg_ops; + struct ffa_send_direct_data data; + struct ffa_mem_region_attributes *mem_attr; + struct ffa_mem_ops_args args = { + .use_txbuf = true, + .tag = use_case, + }; + struct page *page; + struct scatterlist sgl; + unsigned int n; + int rc; + + mem_attr = kcalloc(ep_count, sizeof(*mem_attr), GFP_KERNEL); + for (n = 0; n < ep_count; n++) { + mem_attr[n].receiver = end_points[n]; + mem_attr[n].attrs = FFA_MEM_RW; + } + args.attrs = mem_attr; + args.nattrs = ep_count; + + page = phys_to_page(protmem->paddr); + sg_init_table(&sgl, 1); + sg_set_page(&sgl, page, protmem->size, 0); + + args.sg = &sgl; + rc = mem_ops->memory_lend(&args); + kfree(mem_attr); + if (rc) + return rc; + + rc = do_call_lend_protmem(optee, args.g_handle, use_case); + if (rc) + goto err_reclaim; + + rc = optee_shm_add_ffa_handle(optee, protmem, args.g_handle); + if (rc) + goto err_unreg; + + protmem->sec_world_id = args.g_handle; + + return 0; + +err_unreg: + data = (struct ffa_send_direct_data){ + .data0 = OPTEE_FFA_RELEASE_PROTMEM, + .data1 = (u32)args.g_handle, + .data2 = (u32)(args.g_handle >> 32), + }; + msg_ops->sync_send_receive(ffa_dev, &data); +err_reclaim: + mem_ops->memory_reclaim(args.g_handle, 0); + return rc; +} + +static int optee_ffa_reclaim_protmem(struct optee *optee, + struct tee_shm *protmem) +{ + struct ffa_device *ffa_dev = optee->ffa.ffa_dev; + const struct ffa_msg_ops *msg_ops = ffa_dev->ops->msg_ops; + const struct ffa_mem_ops *mem_ops = ffa_dev->ops->mem_ops; + u64 global_handle = protmem->sec_world_id; + struct ffa_send_direct_data data = { + .data0 = OPTEE_FFA_RELEASE_PROTMEM, + .data1 = (u32)global_handle, + .data2 = (u32)(global_handle >> 32) + }; + int rc; + + optee_shm_rem_ffa_handle(optee, global_handle); + protmem->sec_world_id = 0; + + rc = msg_ops->sync_send_receive(ffa_dev, &data); + if (rc) + pr_err("Release SHM id 0x%llx rc %d\n", global_handle, rc); + + rc = mem_ops->memory_reclaim(global_handle, 0); + if (rc) + pr_err("mem_reclaim: 0x%llx %d", global_handle, rc); + + return rc; +} + /* * 6. Driver initialization * @@ -833,6 +951,8 @@ static const struct optee_ops optee_ffa_ops = { .do_call_with_arg = optee_ffa_do_call_with_arg, .to_msg_param = optee_ffa_to_msg_param, .from_msg_param = optee_ffa_from_msg_param, + .lend_protmem = optee_ffa_lend_protmem, + .reclaim_protmem = optee_ffa_reclaim_protmem, };
static void optee_ffa_remove(struct ffa_device *ffa_dev) @@ -891,6 +1011,25 @@ static int optee_ffa_async_notif_init(struct ffa_device *ffa_dev, return rc; }
+static int optee_ffa_protmem_pool_init(struct optee *optee, u32 sec_caps) +{ + enum tee_dma_heap_id id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY; + struct tee_protmem_pool *pool; + int rc = 0; + + if (sec_caps & OPTEE_FFA_SEC_CAP_PROTMEM) { + pool = optee_protmem_alloc_cma_pool(optee, id); + if (IS_ERR(pool)) + return PTR_ERR(pool); + + rc = tee_device_register_dma_heap(optee->teedev, id, pool); + if (rc) + pool->ops->destroy_pool(pool); + } + + return rc; +} + static int optee_ffa_probe(struct ffa_device *ffa_dev) { const struct ffa_notifier_ops *notif_ops; @@ -941,7 +1080,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) optee->pool, optee); if (IS_ERR(teedev)) { rc = PTR_ERR(teedev); - goto err_free_pool; + goto err_free_shm_pool; } optee->teedev = teedev;
@@ -988,6 +1127,9 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) rc); }
+ if (optee_ffa_protmem_pool_init(optee, sec_caps)) + pr_info("Protected memory service not available\n"); + rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES); if (rc) goto err_unregister_devices; @@ -1001,6 +1143,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev)
err_unregister_devices: optee_unregister_devices(); + tee_device_unregister_all_dma_heaps(optee->teedev); if (optee->ffa.bottom_half_value != U32_MAX) notif_ops->notify_relinquish(ffa_dev, optee->ffa.bottom_half_value); @@ -1018,7 +1161,7 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) tee_device_unregister(optee->supp_teedev); err_unreg_teedev: tee_device_unregister(optee->teedev); -err_free_pool: +err_free_shm_pool: tee_shm_pool_free(pool); err_free_optee: kfree(optee); diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index 20eda508dbac..7c53433f6562 100644 --- a/drivers/tee/optee/optee_private.h +++ b/drivers/tee/optee/optee_private.h @@ -174,9 +174,14 @@ struct optee; * @do_call_with_arg: enters OP-TEE in secure world * @to_msg_param: converts from struct tee_param to OPTEE_MSG parameters * @from_msg_param: converts from OPTEE_MSG parameters to struct tee_param + * @lend_protmem: lends physically contiguous memory as restricted + * memory, inaccessible by the kernel + * @reclaim_protmem: reclaims restricted memory previously lent with + * @lend_protmem() and makes it accessible by the + * kernel again * * These OPs are only supposed to be used internally in the OP-TEE driver - * as a way of abstracting the different methogs of entering OP-TEE in + * as a way of abstracting the different methods of entering OP-TEE in * secure world. */ struct optee_ops { @@ -191,6 +196,10 @@ struct optee_ops { size_t num_params, const struct optee_msg_param *msg_params, bool update_out); + int (*lend_protmem)(struct optee *optee, struct tee_shm *protmem, + u16 *end_points, unsigned int ep_count, + u32 use_case); + int (*reclaim_protmem)(struct optee *optee, struct tee_shm *protmem); };
/** @@ -285,6 +294,8 @@ u32 optee_supp_thrd_req(struct tee_context *ctx, u32 func, size_t num_params, void optee_supp_init(struct optee_supp *supp); void optee_supp_uninit(struct optee_supp *supp); void optee_supp_release(struct optee_supp *supp); +struct tee_protmem_pool *optee_protmem_alloc_cma_pool(struct optee *optee, + enum tee_dma_heap_id id);
int optee_supp_recv(struct tee_context *ctx, u32 *func, u32 *num_params, struct tee_param *param); diff --git a/drivers/tee/optee/protmem.c b/drivers/tee/optee/protmem.c new file mode 100644 index 000000000000..e8d6b750a881 --- /dev/null +++ b/drivers/tee/optee/protmem.c @@ -0,0 +1,330 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2025, Linaro Limited + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/errno.h> +#include <linux/genalloc.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/tee_core.h> +#include <linux/types.h> +#include "optee_private.h" + +struct optee_protmem_cma_pool { + struct tee_protmem_pool pool; + struct gen_pool *gen_pool; + struct optee *optee; + size_t page_count; + u16 *end_points; + u_int end_point_count; + u_int align; + refcount_t refcount; + u32 use_case; + struct tee_shm *protmem; + /* Protects when initializing and tearing down this struct */ + struct mutex mutex; +}; + +static struct optee_protmem_cma_pool * +to_protmem_cma_pool(struct tee_protmem_pool *pool) +{ + return container_of(pool, struct optee_protmem_cma_pool, pool); +} + +static int init_cma_protmem(struct optee_protmem_cma_pool *rp) +{ + int rc; + + rp->protmem = tee_shm_alloc_cma_phys_mem(rp->optee->ctx, rp->page_count, + rp->align); + if (IS_ERR(rp->protmem)) { + rc = PTR_ERR(rp->protmem); + goto err_null_protmem; + } + + /* + * TODO unmap the memory range since the physical memory will + * become inaccesible after the lend_protmem() call. + */ + rc = rp->optee->ops->lend_protmem(rp->optee, rp->protmem, + rp->end_points, + rp->end_point_count, rp->use_case); + if (rc) + goto err_put_shm; + rp->protmem->flags |= TEE_SHM_DYNAMIC; + + rp->gen_pool = gen_pool_create(PAGE_SHIFT, -1); + if (!rp->gen_pool) { + rc = -ENOMEM; + goto err_reclaim; + } + + rc = gen_pool_add(rp->gen_pool, rp->protmem->paddr, + rp->protmem->size, -1); + if (rc) + goto err_free_pool; + + refcount_set(&rp->refcount, 1); + return 0; + +err_free_pool: + gen_pool_destroy(rp->gen_pool); + rp->gen_pool = NULL; +err_reclaim: + rp->optee->ops->reclaim_protmem(rp->optee, rp->protmem); +err_put_shm: + tee_shm_put(rp->protmem); +err_null_protmem: + rp->protmem = NULL; + return rc; +} + +static int get_cma_protmem(struct optee_protmem_cma_pool *rp) +{ + int rc = 0; + + if (!refcount_inc_not_zero(&rp->refcount)) { + mutex_lock(&rp->mutex); + if (rp->gen_pool) { + /* + * Another thread has already initialized the pool + * before us, or the pool was just about to be torn + * down. Either way we only need to increase the + * refcount and we're done. + */ + refcount_inc(&rp->refcount); + } else { + rc = init_cma_protmem(rp); + } + mutex_unlock(&rp->mutex); + } + + return rc; +} + +static void release_cma_protmem(struct optee_protmem_cma_pool *rp) +{ + gen_pool_destroy(rp->gen_pool); + rp->gen_pool = NULL; + + rp->optee->ops->reclaim_protmem(rp->optee, rp->protmem); + rp->protmem->flags &= ~TEE_SHM_DYNAMIC; + + WARN(refcount_read(&rp->protmem->refcount) != 1, "Unexpected refcount"); + tee_shm_put(rp->protmem); + rp->protmem = NULL; +} + +static void put_cma_protmem(struct optee_protmem_cma_pool *rp) +{ + if (refcount_dec_and_test(&rp->refcount)) { + mutex_lock(&rp->mutex); + if (rp->gen_pool) + release_cma_protmem(rp); + mutex_unlock(&rp->mutex); + } +} + +static int protmem_pool_op_cma_alloc(struct tee_protmem_pool *pool, + struct sg_table *sgt, size_t size, + size_t *offs) +{ + struct optee_protmem_cma_pool *rp = to_protmem_cma_pool(pool); + size_t sz = ALIGN(size, PAGE_SIZE); + phys_addr_t pa; + int rc; + + rc = get_cma_protmem(rp); + if (rc) + return rc; + + pa = gen_pool_alloc(rp->gen_pool, sz); + if (!pa) { + rc = -ENOMEM; + goto err_put; + } + + rc = sg_alloc_table(sgt, 1, GFP_KERNEL); + if (rc) + goto err_free; + + sg_set_page(sgt->sgl, phys_to_page(pa), size, 0); + *offs = pa - rp->protmem->paddr; + + return 0; +err_free: + gen_pool_free(rp->gen_pool, pa, size); +err_put: + put_cma_protmem(rp); + + return rc; +} + +static void protmem_pool_op_cma_free(struct tee_protmem_pool *pool, + struct sg_table *sgt) +{ + struct optee_protmem_cma_pool *rp = to_protmem_cma_pool(pool); + struct scatterlist *sg; + int i; + + for_each_sgtable_sg(sgt, sg, i) + gen_pool_free(rp->gen_pool, sg_phys(sg), sg->length); + sg_free_table(sgt); + put_cma_protmem(rp); +} + +static int protmem_pool_op_cma_update_shm(struct tee_protmem_pool *pool, + struct sg_table *sgt, size_t offs, + struct tee_shm *shm, + struct tee_shm **parent_shm) +{ + struct optee_protmem_cma_pool *rp = to_protmem_cma_pool(pool); + + *parent_shm = rp->protmem; + + return 0; +} + +static void pool_op_cma_destroy_pool(struct tee_protmem_pool *pool) +{ + struct optee_protmem_cma_pool *rp = to_protmem_cma_pool(pool); + + mutex_destroy(&rp->mutex); + kfree(rp); +} + +static struct tee_protmem_pool_ops protmem_pool_ops_cma = { + .alloc = protmem_pool_op_cma_alloc, + .free = protmem_pool_op_cma_free, + .update_shm = protmem_pool_op_cma_update_shm, + .destroy_pool = pool_op_cma_destroy_pool, +}; + +static int get_protmem_config(struct optee *optee, u32 use_case, + size_t *min_size, u_int *min_align, + u16 *end_points, u_int *ep_count) +{ + struct tee_param params[2] = { + [0] = { + .attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT, + .u.value.a = use_case, + }, + [1] = { + .attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT, + }, + }; + struct optee_shm_arg_entry *entry; + struct tee_shm *shm_param = NULL; + struct optee_msg_arg *msg_arg; + struct tee_shm *shm; + u_int offs; + int rc; + + if (end_points && *ep_count) { + params[1].u.memref.size = *ep_count * sizeof(*end_points); + shm_param = tee_shm_alloc_priv_buf(optee->ctx, + params[1].u.memref.size); + if (IS_ERR(shm_param)) + return PTR_ERR(shm_param); + params[1].u.memref.shm = shm_param; + } + + msg_arg = optee_get_msg_arg(optee->ctx, ARRAY_SIZE(params), &entry, + &shm, &offs); + if (IS_ERR(msg_arg)) { + rc = PTR_ERR(msg_arg); + goto out_free_shm; + } + msg_arg->cmd = OPTEE_MSG_CMD_GET_PROTMEM_CONFIG; + + rc = optee->ops->to_msg_param(optee, msg_arg->params, + ARRAY_SIZE(params), params, + false /*!update_out*/); + if (rc) + goto out_free_msg; + + rc = optee->ops->do_call_with_arg(optee->ctx, shm, offs, false); + if (rc) + goto out_free_msg; + if (msg_arg->ret && msg_arg->ret != TEEC_ERROR_SHORT_BUFFER) { + rc = -EINVAL; + goto out_free_msg; + } + + rc = optee->ops->from_msg_param(optee, params, ARRAY_SIZE(params), + msg_arg->params, true /*update_out*/); + if (rc) + goto out_free_msg; + + if (!msg_arg->ret && end_points && + *ep_count < params[1].u.memref.size / sizeof(u16)) { + rc = -EINVAL; + goto out_free_msg; + } + + *min_size = params[0].u.value.a; + *min_align = params[0].u.value.b; + *ep_count = params[1].u.memref.size / sizeof(u16); + + if (msg_arg->ret == TEEC_ERROR_SHORT_BUFFER) { + rc = -ENOSPC; + goto out_free_msg; + } + + if (end_points) + memcpy(end_points, tee_shm_get_va(shm_param, 0), + params[1].u.memref.size); + +out_free_msg: + optee_free_msg_arg(optee->ctx, entry, offs); +out_free_shm: + if (shm_param) + tee_shm_free(shm_param); + return rc; +} + +struct tee_protmem_pool *optee_protmem_alloc_cma_pool(struct optee *optee, + enum tee_dma_heap_id id) +{ + struct optee_protmem_cma_pool *rp; + u32 use_case = id; + size_t min_size; + int rc; + + rp = kzalloc(sizeof(*rp), GFP_KERNEL); + if (!rp) + return ERR_PTR(-ENOMEM); + rp->use_case = use_case; + + rc = get_protmem_config(optee, use_case, &min_size, &rp->align, NULL, + &rp->end_point_count); + if (rc) { + if (rc != -ENOSPC) + goto err; + rp->end_points = kcalloc(rp->end_point_count, + sizeof(*rp->end_points), GFP_KERNEL); + if (!rp->end_points) { + rc = -ENOMEM; + goto err; + } + rc = get_protmem_config(optee, use_case, &min_size, &rp->align, + rp->end_points, &rp->end_point_count); + if (rc) + goto err_kfree_eps; + } + + rp->pool.ops = &protmem_pool_ops_cma; + rp->optee = optee; + rp->page_count = min_size / PAGE_SIZE; + mutex_init(&rp->mutex); + + return &rp->pool; + +err_kfree_eps: + kfree(rp->end_points); +err: + kfree(rp); + return ERR_PTR(rc); +}