From: Volodymyr Babchuk vlad.babchuk@gmail.com
With latest changes to OP-TEE we can use any buffers as a shared memory. Thus, it is possible for supplicant to provide part of own memory when OP-TEE asks to allocate a shared buffer.
This patch adds support for such feature into RPC handling code. Now when OP-TEE asks supplicant to allocate shared buffer, supplicant can use TEE_IOC_SHM_REGISTER to provide such buffer. RPC handler is aware of this, so it will pass list of allocated pages to OP-TEE.
Signed-off-by: Volodymyr Babchuk vlad.babchuk@gmail.com --- drivers/tee/optee/call.c | 19 +++++++++- drivers/tee/optee/core.c | 2 + drivers/tee/optee/optee_private.h | 15 +++++++- drivers/tee/optee/rpc.c | 77 ++++++++++++++++++++++++++++++++++----- 4 files changed, 102 insertions(+), 11 deletions(-)
diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index 89116a0..969045b 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -136,6 +136,7 @@ u32 optee_do_call_with_arg(struct tee_context *ctx, phys_addr_t parg) struct optee *optee = tee_get_drvdata(ctx->teedev); struct optee_call_waiter w; struct optee_rpc_param param = { }; + struct optee_call_ctx call_ctx = { }; u32 ret;
param.a0 = OPTEE_SMC_CALL_WITH_ARG; @@ -160,13 +161,14 @@ u32 optee_do_call_with_arg(struct tee_context *ctx, phys_addr_t parg) param.a1 = res.a1; param.a2 = res.a2; param.a3 = res.a3; - optee_handle_rpc(ctx, ¶m); + optee_handle_rpc(ctx, ¶m, &call_ctx); } else { ret = res.a0; break; } }
+ optee_rpc_finalize_call(&call_ctx); /* * We're done with our thread in secure world, if there's any * thread waiters wake up one. @@ -602,3 +604,18 @@ int optee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm) tee_shm_free(shm_arg); return rc; } + +int optee_shm_register_supp(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages) +{ + /* + * We don't want to register supplicant memory in OP-TEE. + * Instead information about it will be passed in RPC code. + */ + return 0; +} + +int optee_shm_unregister_supp(struct tee_context *ctx, struct tee_shm *shm) +{ + return 0; +} diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c index 3729ebb..d22433c 100644 --- a/drivers/tee/optee/core.c +++ b/drivers/tee/optee/core.c @@ -331,6 +331,8 @@ static const struct tee_driver_ops optee_supp_ops = { .release = optee_release, .supp_recv = optee_supp_recv, .supp_send = optee_supp_send, + .shm_register = optee_shm_register_supp, + .shm_unregister = optee_shm_unregister_supp, };
static const struct tee_desc optee_supp_desc = { diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index d7bc77d..61a0052 100644 --- a/drivers/tee/optee/optee_private.h +++ b/drivers/tee/optee/optee_private.h @@ -130,7 +130,16 @@ struct optee_rpc_param { u32 a7; };
-void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param); +/* Holds context that is preserved during one STD call */ +struct optee_call_ctx { + /* information about pages list used in last allocation */ + void *pages_list; + size_t num_entries; +}; + +void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param, + struct optee_call_ctx *call_ctx); +void optee_rpc_finalize_call(struct optee_call_ctx *call_ctx);
void optee_wait_queue_init(struct optee_wait_queue *wq); void optee_wait_queue_exit(struct optee_wait_queue *wq); @@ -164,6 +173,10 @@ int optee_shm_register(struct tee_context *ctx, struct tee_shm *shm, struct page **pages, size_t num_pages); int optee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm);
+int optee_shm_register_supp(struct tee_context *ctx, struct tee_shm *shm, + struct page **pages, size_t num_pages); +int optee_shm_unregister_supp(struct tee_context *ctx, struct tee_shm *shm); + int optee_from_msg_param(struct tee_param *params, size_t num_params, const struct optee_msg_param *msg_params); int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params, diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c index cef417f..7bd18e3 100644 --- a/drivers/tee/optee/rpc.c +++ b/drivers/tee/optee/rpc.c @@ -200,7 +200,8 @@ static struct tee_shm *cmd_alloc_suppl(struct tee_context *ctx, size_t sz) }
static void handle_rpc_func_cmd_shm_alloc(struct tee_context *ctx, - struct optee_msg_arg *arg) + struct optee_msg_arg *arg, + struct optee_call_ctx *call_ctx) { phys_addr_t pa; struct tee_shm *shm; @@ -245,10 +246,49 @@ static void handle_rpc_func_cmd_shm_alloc(struct tee_context *ctx, goto bad; }
- arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT; - arg->params[0].u.tmem.buf_ptr = pa; - arg->params[0].u.tmem.size = sz; - arg->params[0].u.tmem.shm_ref = (unsigned long)shm; + sz = tee_shm_get_size(shm); + + if (tee_shm_is_registered(shm)) { + struct page **pages; + u64 *pages_list; + size_t page_num; + + pages = tee_shm_get_pages(shm, &page_num); + if (!pages || !page_num) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + goto bad; + } + + pages_list = optee_allocate_pages_list(page_num); + if (!pages_list) { + arg->ret = TEEC_ERROR_OUT_OF_MEMORY; + goto bad; + } + + call_ctx->pages_list = pages_list; + call_ctx->num_entries = page_num; + + arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT | + OPTEE_MSG_ATTR_NONCONTIG; + /* + * In the least bits of u.tmem.buf_ptr we store buffer offset + * from 4k page, as described in OP-TEE ABI. + */ + arg->params[0].u.tmem.buf_ptr = virt_to_phys(pages_list) | + (tee_shm_get_page_offset(shm) & + (OPTEE_MSG_NONCONTIG_PAGE_SIZE - 1)); + arg->params[0].u.tmem.size = tee_shm_get_size(shm); + arg->params[0].u.tmem.shm_ref = (unsigned long)shm; + + optee_fill_pages_list(pages_list, pages, page_num, + tee_shm_get_page_offset(shm)); + } else { + arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT; + arg->params[0].u.tmem.buf_ptr = pa; + arg->params[0].u.tmem.size = sz; + arg->params[0].u.tmem.shm_ref = (unsigned long)shm; + } + arg->ret = TEEC_SUCCESS; return; bad: @@ -307,8 +347,24 @@ static void handle_rpc_func_cmd_shm_free(struct tee_context *ctx, arg->ret = TEEC_SUCCESS; }
+static void free_pages_list(struct optee_call_ctx *call_ctx) +{ + if (call_ctx->pages_list) { + optee_free_pages_list(call_ctx->pages_list, + call_ctx->num_entries); + call_ctx->pages_list = NULL; + call_ctx->num_entries = 0; + } +} + +void optee_rpc_finalize_call(struct optee_call_ctx *call_ctx) +{ + free_pages_list(call_ctx); +} + static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, - struct tee_shm *shm) + struct tee_shm *shm, + struct optee_call_ctx *call_ctx) { struct optee_msg_arg *arg;
@@ -329,7 +385,8 @@ static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, handle_rpc_func_cmd_wait(arg); break; case OPTEE_MSG_RPC_CMD_SHM_ALLOC: - handle_rpc_func_cmd_shm_alloc(ctx, arg); + free_pages_list(call_ctx); + handle_rpc_func_cmd_shm_alloc(ctx, arg, call_ctx); break; case OPTEE_MSG_RPC_CMD_SHM_FREE: handle_rpc_func_cmd_shm_free(ctx, arg); @@ -343,10 +400,12 @@ static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, * optee_handle_rpc() - handle RPC from secure world * @ctx: context doing the RPC * @param: value of registers for the RPC + * @call_ctx: call context. Preserved during one OP-TEE invocation * * Result of RPC is written back into @param. */ -void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param) +void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param, + struct optee_call_ctx *call_ctx) { struct tee_device *teedev = ctx->teedev; struct optee *optee = tee_get_drvdata(teedev); @@ -381,7 +440,7 @@ void optee_handle_rpc(struct tee_context *ctx, struct optee_rpc_param *param) break; case OPTEE_SMC_RPC_FUNC_CMD: shm = reg_pair_to_ptr(param->a1, param->a2); - handle_rpc_func_cmd(ctx, optee, shm); + handle_rpc_func_cmd(ctx, optee, shm, call_ctx); break; default: pr_warn("Unknown RPC func 0x%x\n",