Hi Sumit, On Tue, Mar 25, 2025 at 8:42 AM Sumit Garg <sumit.g...@kernel.org> wrote: > > On Wed, Mar 05, 2025 at 02:04:15PM +0100, Jens Wiklander wrote: > > 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.wiklan...@linaro.org> > > --- > > drivers/tee/optee/Makefile | 1 + > > drivers/tee/optee/ffa_abi.c | 143 ++++++++++++- > > drivers/tee/optee/optee_private.h | 13 +- > > drivers/tee/optee/rstmem.c | 329 ++++++++++++++++++++++++++++++ > > 4 files changed, 483 insertions(+), 3 deletions(-) > > create mode 100644 drivers/tee/optee/rstmem.c > > > > diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile > > index a6eff388d300..498969fb8e40 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 += rstmem.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..6a55114232ef 100644 > > --- a/drivers/tee/optee/ffa_abi.c > > +++ b/drivers/tee/optee/ffa_abi.c > > @@ -672,6 +672,123 @@ 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, > > + 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(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, 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 > > * > > @@ -833,6 +950,8 @@ 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) > > @@ -941,7 +1060,7 @@ 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 +1107,24 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) > > rc); > > } > > > > + if (IS_ENABLED(CONFIG_CMA) && !IS_MODULE(CONFIG_OPTEE) && > > The CMA dependency should be managed via Kconfig.
Yes, I'll fix it. > > > + (sec_caps & OPTEE_FFA_SEC_CAP_RSTMEM)) { > > + enum tee_dma_heap_id id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY; > > + struct tee_rstmem_pool *pool; > > + > > + pool = optee_rstmem_alloc_cma_pool(optee, id); > > + if (IS_ERR(pool)) { > > + rc = PTR_ERR(pool); > > + goto err_notif_uninit; > > + } > > + > > + rc = tee_device_register_dma_heap(optee->teedev, id, pool); > > + if (rc) { > > + pool->ops->destroy_pool(pool); > > + goto err_notif_uninit; > > + } > > + } > > + > > rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES); > > if (rc) > > goto err_unregister_devices; > > @@ -1001,6 +1138,8 @@ static int optee_ffa_probe(struct ffa_device *ffa_dev) > > > > err_unregister_devices: > > optee_unregister_devices(); > > + tee_device_unregister_all_dma_heaps(optee->teedev); > > +err_notif_uninit: > > if (optee->ffa.bottom_half_value != U32_MAX) > > notif_ops->notify_relinquish(ffa_dev, > > optee->ffa.bottom_half_value); > > @@ -1018,7 +1157,7 @@ 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..faab31ad7c52 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 +196,10 @@ 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, > > + u32 use_case); > > + int (*reclaim_rstmem)(struct optee *optee, struct tee_shm *rstmem); > > }; > > > > /** > > @@ -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_rstmem_pool *optee_rstmem_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/rstmem.c b/drivers/tee/optee/rstmem.c > > new file mode 100644 > > index 000000000000..ea27769934d4 > > --- /dev/null > > +++ b/drivers/tee/optee/rstmem.c > > @@ -0,0 +1,329 @@ > > +// 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_rstmem_cma_pool { > > + struct tee_rstmem_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 *rstmem; > > + /* Protects when initializing and tearing down this struct */ > > + struct mutex mutex; > > +}; > > + > > +static struct optee_rstmem_cma_pool * > > +to_rstmem_cma_pool(struct tee_rstmem_pool *pool) > > +{ > > + return container_of(pool, struct optee_rstmem_cma_pool, pool); > > +} > > + > > +static int init_cma_rstmem(struct optee_rstmem_cma_pool *rp) > > +{ > > + int rc; > > + > > + rp->rstmem = tee_shm_alloc_cma_phys_mem(rp->optee->ctx, > > rp->page_count, > > + rp->align); > > + if (IS_ERR(rp->rstmem)) { > > + rc = PTR_ERR(rp->rstmem); > > + goto err_null_rstmem; > > + } > > + > > + /* > > + * TODO unmap the memory range since the physical memory will > > + * become inaccesible after the lend_rstmem() call. > > + */ > > What's your plan for this TODO? I think we need a CMA allocator here > which can allocate un-mapped memory such that any cache speculation > won't lead to CPU hangs once the memory restriction comes into picture. What happens is platform-specific. For some platforms, it might be enough to avoid explicit access. Yes, a CMA allocator with unmapped memory or where memory can be unmapped is one option. > > > + rc = rp->optee->ops->lend_rstmem(rp->optee, rp->rstmem, > > rp->end_points, > > + rp->end_point_count, rp->use_case); > > + if (rc) > > + goto err_put_shm; > > + rp->rstmem->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->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->gen_pool); > > + rp->gen_pool = NULL; > > +err_reclaim: > > + rp->optee->ops->reclaim_rstmem(rp->optee, rp->rstmem); > > +err_put_shm: > > + tee_shm_put(rp->rstmem); > > +err_null_rstmem: > > + rp->rstmem = NULL; > > + 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->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_rstmem(rp); > > + } > > + mutex_unlock(&rp->mutex); > > + } > > + > > + return rc; > > +} > > + > > +static void release_cma_rstmem(struct optee_rstmem_cma_pool *rp) > > +{ > > + gen_pool_destroy(rp->gen_pool); > > + rp->gen_pool = NULL; > > + > > + rp->optee->ops->reclaim_rstmem(rp->optee, rp->rstmem); > > + rp->rstmem->flags &= ~TEE_SHM_DYNAMIC; > > + > > + WARN(refcount_read(&rp->rstmem->refcount) != 1, "Unexpected > > refcount"); > > + tee_shm_put(rp->rstmem); > > + rp->rstmem = NULL; > > +} > > + > > +static void put_cma_rstmem(struct optee_rstmem_cma_pool *rp) > > +{ > > + if (refcount_dec_and_test(&rp->refcount)) { > > + mutex_lock(&rp->mutex); > > + if (rp->gen_pool) > > + release_cma_rstmem(rp); > > + mutex_unlock(&rp->mutex); > > + } > > +} > > + > > +static int rstmem_pool_op_cma_alloc(struct tee_rstmem_pool *pool, > > + struct sg_table *sgt, size_t size, > > + size_t *offs) > > +{ > > + 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->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->rstmem->paddr; > > + > > + return 0; > > +err_free: > > + gen_pool_free(rp->gen_pool, pa, size); > > +err_put: > > + put_cma_rstmem(rp); > > + > > + return rc; > > +} > > + > > +static void rstmem_pool_op_cma_free(struct tee_rstmem_pool *pool, > > + struct sg_table *sgt) > > +{ > > + struct optee_rstmem_cma_pool *rp = to_rstmem_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_rstmem(rp); > > +} > > + > > +static int rstmem_pool_op_cma_update_shm(struct tee_rstmem_pool *pool, > > + struct sg_table *sgt, size_t offs, > > + struct tee_shm *shm, > > + struct tee_shm **parent_shm) > > +{ > > + struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool); > > + > > + *parent_shm = rp->rstmem; > > + > > + return 0; > > +} > > + > > +static void pool_op_cma_destroy_pool(struct tee_rstmem_pool *pool) > > +{ > > + struct optee_rstmem_cma_pool *rp = to_rstmem_cma_pool(pool); > > + > > + mutex_destroy(&rp->mutex); > > + kfree(rp); > > +} > > + > > +static struct tee_rstmem_pool_ops rstmem_pool_ops_cma = { > > + .alloc = rstmem_pool_op_cma_alloc, > > + .free = rstmem_pool_op_cma_free, > > + .update_shm = rstmem_pool_op_cma_update_shm, > > + .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) > > I guess this end points terminology is specific to FF-A ABI. Is there > any relevance for this in the common APIs? Yes, endpoints are specific to FF-A ABI. The list of end-points must be presented to FFA_MEM_LEND. We're relying on the secure world to know which endpoints are needed for a specific use case. Cheers, Jens > > -Sumit > > > +{ > > + 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; > > +} > > + > > +struct tee_rstmem_pool *optee_rstmem_alloc_cma_pool(struct optee *optee, > > + enum tee_dma_heap_id id) > > +{ > > + struct optee_rstmem_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_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); > > +} > > -- > > 2.43.0 > >