Hi Sumit,
On Tue, Mar 25, 2025 at 8:42 AM Sumit Garg sumit.garg@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.wiklander@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;+}
/*
- 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