Add support in the OP-TEE backend driver dynamic restricted memory allocation with FF-A.
The restricted memory pools for dynamically allocated restrict memory are instantiated when requested by user-space. This instantiation can fail if OP-TEE doesn't support the requested use-case of restricted 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/ffa_abi.c | 136 ++++++++++++- drivers/tee/optee/optee_private.h | 10 +- drivers/tee/optee/rstmem.c | 317 +++++++++++++++++++++++++++++- 3 files changed, 459 insertions(+), 4 deletions(-)
diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c index 02e6175ac5f0..b933f12d096e 100644 --- a/drivers/tee/optee/ffa_abi.c +++ b/drivers/tee/optee/ffa_abi.c @@ -672,6 +672,122 @@ 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_rstmem(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_RSTMEM; + 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_rstmem(struct optee *optee, struct tee_shm *rstmem, + u16 *end_points, unsigned int ep_count) +{ + 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 = rstmem->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(rstmem->paddr); + sg_init_table(&sgl, 1); + sg_set_page(&sgl, page, rstmem->size, 0); + + args.sg = &sgl; + rc = mem_ops->memory_lend(&args); + kfree(mem_attr); + if (rc) + return rc; + + rc = do_call_lend_rstmem(optee, args.g_handle, rstmem->use_case); + if (rc) + goto err_reclaim; + + rc = optee_shm_add_ffa_handle(optee, rstmem, args.g_handle); + if (rc) + goto err_unreg; + + rstmem->sec_world_id = args.g_handle; + + return 0; + +err_unreg: + data = (struct ffa_send_direct_data){ + .data0 = OPTEE_FFA_RELEASE_RSTMEM, + .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_rstmem(struct optee *optee, struct tee_shm *rstmem) +{ + 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 = rstmem->sec_world_id; + struct ffa_send_direct_data data = { + .data0 = OPTEE_FFA_RELEASE_RSTMEM, + .data1 = (u32)global_handle, + .data2 = (u32)(global_handle >> 32) + }; + int rc; + + optee_shm_rem_ffa_handle(optee, global_handle); + rstmem->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 * @@ -785,7 +901,10 @@ static void optee_ffa_get_version(struct tee_device *teedev, .gen_caps = TEE_GEN_CAP_GP | TEE_GEN_CAP_REG_MEM | TEE_GEN_CAP_MEMREF_NULL, }; + struct optee *optee = tee_get_drvdata(teedev);
+ if (optee->rstmem_pools) + v.gen_caps |= TEE_GEN_CAP_RSTMEM; *vers = v; }
@@ -804,6 +923,8 @@ static const struct tee_driver_ops optee_ffa_clnt_ops = { .cancel_req = optee_cancel_req, .shm_register = optee_ffa_shm_register, .shm_unregister = optee_ffa_shm_unregister, + .rstmem_alloc = optee_rstmem_alloc, + .rstmem_free = optee_rstmem_free, };
static const struct tee_desc optee_ffa_clnt_desc = { @@ -820,6 +941,8 @@ static const struct tee_driver_ops optee_ffa_supp_ops = { .supp_send = optee_supp_send, .shm_register = optee_ffa_shm_register, /* same as for clnt ops */ .shm_unregister = optee_ffa_shm_unregister_supp, + .rstmem_alloc = optee_rstmem_alloc, + .rstmem_free = optee_rstmem_free, };
static const struct tee_desc optee_ffa_supp_desc = { @@ -833,6 +956,8 @@ 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_rstmem = optee_ffa_lend_rstmem, + .reclaim_rstmem = optee_ffa_reclaim_rstmem, };
static void optee_ffa_remove(struct ffa_device *ffa_dev) @@ -937,11 +1062,18 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) (sec_caps & OPTEE_FFA_SEC_CAP_RPMB_PROBE)) optee->in_kernel_rpmb_routing = true;
+ if (IS_ENABLED(CONFIG_CMA) && !IS_MODULE(CONFIG_OPTEE) && + (sec_caps & OPTEE_FFA_SEC_CAP_RSTMEM)) { + rc = optee_rstmem_pools_init(optee); + if (rc) + goto err_free_pool; + } + teedev = tee_device_alloc(&optee_ffa_clnt_desc, NULL, optee->pool, optee); if (IS_ERR(teedev)) { rc = PTR_ERR(teedev); - goto err_free_pool; + goto err_free_rstmem_pools; } optee->teedev = teedev;
@@ -1020,6 +1152,8 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) tee_device_unregister(optee->teedev); err_free_pool: tee_shm_pool_free(pool); +err_free_rstmem_pools: + optee_rstmem_pools_uninit(optee); err_free_optee: kfree(optee); return rc; diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index 0491889e5b0e..dd2a3a2224bc 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_rstmem: lends physically contiguous memory as restricted + * memory, inaccessible by the kernel + * @reclaim_rstmem: reclaims restricted memory previously lent with + * @lend_rstmem() 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 +196,9 @@ struct optee_ops { size_t num_params, const struct optee_msg_param *msg_params, bool update_out); + int (*lend_rstmem)(struct optee *optee, struct tee_shm *rstmem, + u16 *end_points, unsigned int ep_count); + int (*reclaim_rstmem)(struct optee *optee, struct tee_shm *rstmem); };
/** diff --git a/drivers/tee/optee/rstmem.c b/drivers/tee/optee/rstmem.c index 01456bc3e2f6..9a5013e3cc5f 100644 --- a/drivers/tee/optee/rstmem.c +++ b/drivers/tee/optee/rstmem.c @@ -4,6 +4,7 @@ */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/cma.h> #include <linux/dma-map-ops.h> #include <linux/errno.h> #include <linux/genalloc.h> @@ -13,11 +14,314 @@ #include <linux/types.h> #include "optee_private.h"
+#if IS_ENABLED(CONFIG_CMA) && !IS_MODULE(CONFIG_OPTEE) +struct optee_rstmem_cma_pool { + struct tee_shm_pool pool; + struct page *page; + struct optee *optee; + size_t page_count; + u16 *end_points; + u_int end_point_count; + u_int align; + refcount_t refcount; + struct tee_shm rstmem; + /* Protects when initializing and tearing down this struct */ + struct mutex mutex; +}; + +static struct optee_rstmem_cma_pool * +to_rstmem_cma_pool(struct tee_shm_pool *pool) +{ + return container_of(pool, struct optee_rstmem_cma_pool, pool); +} + +static int init_cma_rstmem(struct optee_rstmem_cma_pool *rp) +{ + struct cma *cma = dev_get_cma_area(&rp->optee->teedev->dev); + int rc; + + rp->page = cma_alloc(cma, rp->page_count, rp->align, true/*no_warn*/); + if (!rp->page) + return -ENOMEM; + + /* + * TODO unmap the memory range since the physical memory will + * become inaccesible after the lend_rstmem() call. + */ + + rp->rstmem.paddr = page_to_phys(rp->page); + rp->rstmem.size = rp->page_count * PAGE_SIZE; + rc = rp->optee->ops->lend_rstmem(rp->optee, &rp->rstmem, + rp->end_points, rp->end_point_count); + if (rc) + goto err_release; + + rp->pool.private_data = gen_pool_create(PAGE_SHIFT, -1); + if (!rp->pool.private_data) { + rc = -ENOMEM; + goto err_reclaim; + } + + rc = gen_pool_add(rp->pool.private_data, rp->rstmem.paddr, + rp->rstmem.size, -1); + if (rc) + goto err_free_pool; + + refcount_set(&rp->refcount, 1); + return 0; + +err_free_pool: + gen_pool_destroy(rp->pool.private_data); +err_reclaim: + rp->optee->ops->reclaim_rstmem(rp->optee, &rp->rstmem); +err_release: + cma_release(cma, rp->page, rp->page_count); + rp->rstmem.paddr = 0; + rp->rstmem.size = 0; + rp->rstmem.sec_world_id = 0; + return rc; +} + +static int get_cma_rstmem(struct optee_rstmem_cma_pool *rp) +{ + int rc = 0; + + if (!refcount_inc_not_zero(&rp->refcount)) { + mutex_lock(&rp->mutex); + if (rp->pool.private_data) { + /* + * 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_rstmem(rp); + } + mutex_unlock(&rp->mutex); + } + + return rc; +} + +static void release_cma_rstmem(struct optee_rstmem_cma_pool *rp) +{ + gen_pool_destroy(rp->pool.private_data); + rp->optee->ops->reclaim_rstmem(rp->optee, &rp->rstmem); + cma_release(dev_get_cma_area(&rp->optee->teedev->dev), rp->page, + rp->page_count); + + rp->pool.private_data = NULL; + rp->page = NULL; + rp->rstmem.paddr = 0; + rp->rstmem.size = 0; + rp->rstmem.sec_world_id = 0; +} + +static void put_cma_rstmem(struct optee_rstmem_cma_pool *rp) +{ + if (refcount_dec_and_test(&rp->refcount)) { + mutex_lock(&rp->mutex); + if (rp->pool.private_data) + release_cma_rstmem(rp); + mutex_unlock(&rp->mutex); + } +} + +static int rstmem_pool_op_cma_alloc(struct tee_shm_pool *pool, + struct tee_shm *shm, size_t size, + size_t align) +{ + struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool); + size_t sz = ALIGN(size, PAGE_SIZE); + phys_addr_t pa; + int rc; + + rc = get_cma_rstmem(rp); + if (rc) + return rc; + + pa = gen_pool_alloc(rp->pool.private_data, sz); + if (!pa) { + put_cma_rstmem(rp); + return -ENOMEM; + } + + shm->size = sz; + shm->paddr = pa; + shm->offset = pa - page_to_phys(rp->page); + shm->sec_world_id = rp->rstmem.sec_world_id; + + return 0; +} + +static void rstmem_pool_op_cma_free(struct tee_shm_pool *pool, + struct tee_shm *shm) +{ + struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool); + + gen_pool_free(rp->pool.private_data, shm->paddr, shm->size); + shm->size = 0; + shm->paddr = 0; + shm->offset = 0; + shm->sec_world_id = 0; + put_cma_rstmem(rp); +} + +static void pool_op_cma_destroy_pool(struct tee_shm_pool *pool) +{ + struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool); + + mutex_destroy(&rp->mutex); + kfree(rp); +} + +static struct tee_shm_pool_ops rstmem_pool_ops_cma = { + .alloc = rstmem_pool_op_cma_alloc, + .free = rstmem_pool_op_cma_free, + .destroy_pool = pool_op_cma_destroy_pool, +}; + +static int get_rstmem_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_RSTMEM_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; +} + +static struct tee_shm_pool *alloc_rstmem_pool(struct optee *optee, u32 use_case) +{ + struct optee_rstmem_cma_pool *rp; + size_t min_size; + int rc; + + rp = kzalloc(sizeof(*rp), GFP_KERNEL); + if (!rp) + return ERR_PTR(-ENOMEM); + rp->rstmem.use_case = use_case; + + rc = get_rstmem_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_rstmem_config(optee, use_case, &min_size, &rp->align, + rp->end_points, &rp->end_point_count); + if (rc) + goto err_kfree_eps; + } + + rp->pool.ops = &rstmem_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); +} +#else /*CONFIG_CMA*/ +static struct tee_shm_pool * +alloc_rstmem_pool(struct optee *optee __always_unused, + u32 use_case __always_unused) +{ + return ERR_PTR(-EINVAL); +} +#endif /*CONFIG_CMA*/ + int optee_rstmem_alloc(struct tee_context *ctx, struct tee_shm *shm, u32 flags, u32 use_case, size_t size) { struct optee *optee = tee_get_drvdata(ctx->teedev); struct tee_shm_pool *pool; + int rc;
if (!optee->rstmem_pools) return -EINVAL; @@ -25,8 +329,17 @@ int optee_rstmem_alloc(struct tee_context *ctx, struct tee_shm *shm, return -EINVAL;
pool = xa_load(&optee->rstmem_pools->xa, use_case); - if (!pool) - return -EINVAL; + if (!pool) { + pool = alloc_rstmem_pool(optee, use_case); + if (IS_ERR(pool)) + return PTR_ERR(pool); + rc = xa_insert(&optee->rstmem_pools->xa, use_case, pool, + GFP_KERNEL); + if (rc) { + pool->ops->destroy_pool(pool); + return rc; + } + }
return pool->ops->alloc(pool, shm, size, 0); }