From ed8faf6c8f8c1f7e9ee88342a915ce5f09ca9736 Mon Sep 17 00:00:00 2001 From: Jens Wiklander Date: Wed, 3 Nov 2021 11:42:30 +0100 Subject: [PATCH] optee: add OPTEE_SMC_CALL_WITH_RPC_ARG and OPTEE_SMC_CALL_WITH_REGD_ARG Adds OPTEE_SMC_CALL_WITH_RPC_ARG and OPTEE_SMC_CALL_WITH_REGD_ARG where the struct optee_msg_arg to be used for RPC is appended in the memory following the normal argument struct optee_msg_arg. This is an optimization to avoid caching the RPC argument struct while still maintaining similar performance as if it was cached. OPTEE_SMC_CALL_WITH_REGD_ARG optimized one step further by using a registered shared memory object instead. It's in other aspects identical to OPTEE_SMC_CALL_WITH_RPC_ARG. The presence of OPTEE_SMC_CALL_WITH_RPC_ARG and OPTEE_SMC_CALL_WITH_REGD_ARG is indicated by the new OPTEE_SMC_SEC_CAP_RPC_ARG bit returned by OPTEE_SMC_EXCHANGE_CAPABILITIES. OPTEE_SMC_EXCHANGE_CAPABILITIES also reports the number of arguments that the RPC argument struct must have room for. OPTEE_SMC_CALL_WITH_RPC_ARG and OPTEE_SMC_CALL_WITH_ARG can be used interleaved with difference that when OPTEE_SMC_CALL_WITH_RPC_ARG is used the RPC argument struct to be used is the one appended to the normal argument struct. The same is true for OPTEE_SMC_CALL_WITH_REGD_ARG. Reviewed-by: Sumit Garg Signed-off-by: Jens Wiklander --- drivers/tee/optee/call.c | 2 +- drivers/tee/optee/optee_smc.h | 48 ++++++++++++++--- drivers/tee/optee/smc_abi.c | 99 ++++++++++++++++++++++++++--------- 3 files changed, 117 insertions(+), 32 deletions(-) diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index a9a237d20c61..58ac15c02818 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -130,7 +130,7 @@ struct tee_shm *optee_get_msg_arg(struct tee_context *ctx, size_t num_params, return (void *)ma; } - memset(ma, 0, OPTEE_MSG_GET_ARG_SIZE(num_params)); + memset(ma, 0, sz); ma->num_params = num_params; *msg_arg = ma; diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index d44a6ae994f8..c60896cf71cb 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -107,14 +107,22 @@ struct optee_smc_call_get_os_revision_result { /* * Call with struct optee_msg_arg as argument * - * When calling this function normal world has a few responsibilities: + * When called with OPTEE_SMC_CALL_WITH_RPC_ARG or + * OPTEE_SMC_CALL_WITH_REGD_ARG in a0 there is one RPC struct optee_msg_arg + * following after the first struct optee_msg_arg. The RPC struct + * optee_msg_arg has reserved space for the number of RPC parameters as + * returned by OPTEE_SMC_EXCHANGE_CAPABILITIES. + * + * When calling these functions, normal world has a few responsibilities: * 1. It must be able to handle eventual RPCs * 2. Non-secure interrupts should not be masked * 3. If asynchronous notifications has been negotiated successfully, then - * asynchronous notifications should be unmasked during this call. + * the interrupt for asynchronous notifications should be unmasked + * during this call. * - * Call register usage: - * a0 SMC Function ID, OPTEE_SMC*CALL_WITH_ARG + * Call register usage, OPTEE_SMC_CALL_WITH_ARG and + * OPTEE_SMC_CALL_WITH_RPC_ARG: + * a0 SMC Function ID, OPTEE_SMC_CALL_WITH_ARG or OPTEE_SMC_CALL_WITH_RPC_ARG * a1 Upper 32 bits of a 64-bit physical pointer to a struct optee_msg_arg * a2 Lower 32 bits of a 64-bit physical pointer to a struct optee_msg_arg * a3 Cache settings, not used if physical pointer is in a predefined shared @@ -122,6 +130,15 @@ struct optee_smc_call_get_os_revision_result { * a4-6 Not used * a7 Hypervisor Client ID register * + * Call register usage, OPTEE_SMC_CALL_WITH_REGD_ARG: + * a0 SMC Function ID, OPTEE_SMC_CALL_WITH_REGD_ARG + * a1 Upper 32 bits of a 64-bit shared memory cookie + * a2 Lower 32 bits of a 64-bit shared memory cookie + * a3 Offset of the struct optee_msg_arg in the shared memory with the + * supplied cookie + * a4-6 Not used + * a7 Hypervisor Client ID register + * * Normal return register usage: * a0 Return value, OPTEE_SMC_RETURN_* * a1-3 Not used @@ -154,6 +171,10 @@ struct optee_smc_call_get_os_revision_result { #define OPTEE_SMC_FUNCID_CALL_WITH_ARG OPTEE_MSG_FUNCID_CALL_WITH_ARG #define OPTEE_SMC_CALL_WITH_ARG \ OPTEE_SMC_STD_CALL_VAL(OPTEE_SMC_FUNCID_CALL_WITH_ARG) +#define OPTEE_SMC_CALL_WITH_RPC_ARG \ + OPTEE_SMC_STD_CALL_VAL(OPTEE_SMC_FUNCID_CALL_WITH_RPC_ARG) +#define OPTEE_SMC_CALL_WITH_REGD_ARG \ + OPTEE_SMC_STD_CALL_VAL(OPTEE_SMC_FUNCID_CALL_WITH_REGD_ARG) /* * Get Shared Memory Config @@ -202,7 +223,11 @@ struct optee_smc_get_shm_config_result { * a0 OPTEE_SMC_RETURN_OK * a1 bitfield of secure world capabilities OPTEE_SMC_SEC_CAP_* * a2 The maximum secure world notification number - * a3-7 Preserved + * a3 Bit[7:0]: Number of parameters needed for RPC to be supplied + * as the second MSG arg struct for + * OPTEE_SMC_CALL_WITH_ARG + * Bit[31:8]: Reserved (MBZ) + * a4-7 Preserved * * Error return register usage: * a0 OPTEE_SMC_RETURN_ENOTAVAIL, can't use the capabilities from normal world @@ -227,6 +252,8 @@ struct optee_smc_get_shm_config_result { #define OPTEE_SMC_SEC_CAP_MEMREF_NULL BIT(4) /* Secure world supports asynchronous notification of normal world */ #define OPTEE_SMC_SEC_CAP_ASYNC_NOTIF BIT(5) +/* Secure world supports pre-allocating RPC arg struct */ +#define OPTEE_SMC_SEC_CAP_RPC_ARG BIT(6) #define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES 9 #define OPTEE_SMC_EXCHANGE_CAPABILITIES \ @@ -236,7 +263,7 @@ struct optee_smc_exchange_capabilities_result { unsigned long status; unsigned long capabilities; unsigned long max_notif_value; - unsigned long reserved0; + unsigned long data; }; /* @@ -358,6 +385,9 @@ struct optee_smc_disable_shm_cache_result { * should be called until all pended values have been retrieved. When a * value is retrieved, it's cleared from the record in secure world. * + * It is expected that this function is called from an interrupt handler + * in normal world. + * * Call requests usage: * a0 SMC Function ID, OPTEE_SMC_GET_ASYNC_NOTIF_VALUE * a1-6 Not used @@ -390,6 +420,12 @@ struct optee_smc_disable_shm_cache_result { #define OPTEE_SMC_GET_ASYNC_NOTIF_VALUE \ OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_ASYNC_NOTIF_VALUE) +/* See OPTEE_SMC_CALL_WITH_RPC_ARG above */ +#define OPTEE_SMC_FUNCID_CALL_WITH_RPC_ARG 18 + +/* See OPTEE_SMC_CALL_WITH_REGD_ARG above */ +#define OPTEE_SMC_FUNCID_CALL_WITH_REGD_ARG 19 + /* * Resume from RPC (for example after processing a foreign interrupt) * diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index 67b7f7d2ff27..b258d7306042 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -732,16 +732,9 @@ static void optee_rpc_finalize_call(struct optee_call_ctx *call_ctx) } static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, - struct tee_shm *shm, + struct optee_msg_arg *arg, struct optee_call_ctx *call_ctx) { - struct optee_msg_arg *arg; - - arg = tee_shm_get_va(shm, 0); - if (IS_ERR(arg)) { - pr_err("%s: tee_shm_get_va %p failed\n", __func__, shm); - return; - } switch (arg->cmd) { case OPTEE_RPC_CMD_SHM_ALLOC: @@ -765,11 +758,13 @@ static void handle_rpc_func_cmd(struct tee_context *ctx, struct optee *optee, * Result of RPC is written back into @param. */ static void optee_handle_rpc(struct tee_context *ctx, + struct optee_msg_arg *rpc_arg, struct optee_rpc_param *param, struct optee_call_ctx *call_ctx) { struct tee_device *teedev = ctx->teedev; struct optee *optee = tee_get_drvdata(teedev); + struct optee_msg_arg *arg; struct tee_shm *shm; phys_addr_t pa; @@ -801,8 +796,19 @@ static void optee_handle_rpc(struct tee_context *ctx, */ break; case OPTEE_SMC_RPC_FUNC_CMD: - shm = reg_pair_to_ptr(param->a1, param->a2); - handle_rpc_func_cmd(ctx, optee, shm, call_ctx); + if (rpc_arg) { + arg = rpc_arg; + } else { + shm = reg_pair_to_ptr(param->a1, param->a2); + arg = tee_shm_get_va(shm, 0); + if (IS_ERR(arg)) { + pr_err("%s: tee_shm_get_va %p failed\n", + __func__, shm); + break; + } + } + + handle_rpc_func_cmd(ctx, optee, arg, call_ctx); break; default: pr_warn("Unknown RPC func 0x%x\n", @@ -816,7 +822,7 @@ static void optee_handle_rpc(struct tee_context *ctx, /** * optee_smc_do_call_with_arg() - Do an SMC to OP-TEE in secure world * @ctx: calling context - * @arg: shared memory holding the message to pass to secure world + * @shm: shared memory holding the message to pass to secure world * * Does and SMC to OP-TEE in secure world and handles eventual resulting * Remote Procedure Calls (RPC) from OP-TEE. @@ -824,21 +830,46 @@ static void optee_handle_rpc(struct tee_context *ctx, * Returns return code from secure world, 0 is OK */ static int optee_smc_do_call_with_arg(struct tee_context *ctx, - struct tee_shm *arg) + struct tee_shm *shm) { struct optee *optee = tee_get_drvdata(ctx->teedev); struct optee_call_waiter w; struct optee_rpc_param param = { }; struct optee_call_ctx call_ctx = { }; - phys_addr_t parg; + struct optee_msg_arg *rpc_arg = NULL; int rc; - rc = tee_shm_get_pa(arg, 0, &parg); - if (rc) - return rc; + if (optee->rpc_param_count) { + struct optee_msg_arg *arg; + unsigned int rpc_arg_offs; - param.a0 = OPTEE_SMC_CALL_WITH_ARG; - reg_pair_from_64(¶m.a1, ¶m.a2, parg); + arg = tee_shm_get_va(shm, 0); + if (IS_ERR(arg)) + return PTR_ERR(arg); + + rpc_arg_offs = OPTEE_MSG_GET_ARG_SIZE(arg->num_params); + rpc_arg = tee_shm_get_va(shm, rpc_arg_offs); + if (IS_ERR(arg)) + return PTR_ERR(arg); + } + + if (rpc_arg && tee_shm_is_dynamic(shm)) { + param.a0 = OPTEE_SMC_CALL_WITH_REGD_ARG; + reg_pair_from_64(¶m.a1, ¶m.a2, (u_long)shm); + param.a3 = 0; + } else { + phys_addr_t parg; + + rc = tee_shm_get_pa(shm, 0, &parg); + if (rc) + return rc; + + if (rpc_arg) + param.a0 = OPTEE_SMC_CALL_WITH_RPC_ARG; + else + param.a0 = OPTEE_SMC_CALL_WITH_ARG; + reg_pair_from_64(¶m.a1, ¶m.a2, parg); + } /* Initialize waiter */ optee_cq_wait_init(&optee->call_queue, &w); while (true) { @@ -862,7 +893,7 @@ static int optee_smc_do_call_with_arg(struct tee_context *ctx, param.a1 = res.a1; param.a2 = res.a2; param.a3 = res.a3; - optee_handle_rpc(ctx, ¶m, &call_ctx); + optee_handle_rpc(ctx, rpc_arg, ¶m, &call_ctx); } else { rc = res.a0; break; @@ -1118,7 +1149,8 @@ static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn) } static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn, - u32 *sec_caps, u32 *max_notif_value) + u32 *sec_caps, u32 *max_notif_value, + unsigned int *rpc_param_count) { union { struct arm_smccc_res smccc; @@ -1145,6 +1177,10 @@ static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn, *max_notif_value = res.result.max_notif_value; else *max_notif_value = OPTEE_DEFAULT_MAX_NOTIF_VALUE; + if (*sec_caps & OPTEE_SMC_SEC_CAP_RPC_ARG) + *rpc_param_count = (u8)res.result.data; + else + *rpc_param_count = 0; return true; } @@ -1251,7 +1287,8 @@ static int optee_smc_remove(struct platform_device *pdev) * reference counters and also avoid wild pointers in secure world * into the old shared memory range. */ - optee_disable_shm_cache(optee); + if (!optee->rpc_param_count) + optee_disable_shm_cache(optee); optee_smc_notif_uninit_irq(optee); @@ -1274,7 +1311,10 @@ static int optee_smc_remove(struct platform_device *pdev) */ static void optee_shutdown(struct platform_device *pdev) { - optee_disable_shm_cache(platform_get_drvdata(pdev)); + struct optee *optee = platform_get_drvdata(pdev); + + if (!optee->rpc_param_count) + optee_disable_shm_cache(optee); } static int optee_probe(struct platform_device *pdev) @@ -1283,6 +1323,7 @@ static int optee_probe(struct platform_device *pdev) struct tee_shm_pool *pool = ERR_PTR(-EINVAL); struct optee *optee = NULL; void *memremaped_shm = NULL; + unsigned int rpc_param_count; struct tee_device *teedev; struct tee_context *ctx; u32 max_notif_value; @@ -1306,7 +1347,8 @@ static int optee_probe(struct platform_device *pdev) } if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps, - &max_notif_value)) { + &max_notif_value, + &rpc_param_count)) { pr_warn("capabilities mismatch\n"); return -EINVAL; } @@ -1335,6 +1377,7 @@ static int optee_probe(struct platform_device *pdev) optee->ops = &optee_ops; optee->smc.invoke_fn = invoke_fn; optee->smc.sec_caps = sec_caps; + optee->rpc_param_count = rpc_param_count; teedev = tee_device_alloc(&optee_clnt_desc, NULL, pool, optee); if (IS_ERR(teedev)) { @@ -1403,7 +1446,12 @@ static int optee_probe(struct platform_device *pdev) */ optee_disable_unmapped_shm_cache(optee); - optee_enable_shm_cache(optee); + /* + * Only enable the shm cache in case we're not able to pass the RPC + * arg struct right after the normal arg struct. + */ + if (!optee->rpc_param_count) + optee_enable_shm_cache(optee); if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) pr_info("dynamic shared memory is enabled\n"); @@ -1416,7 +1464,8 @@ static int optee_probe(struct platform_device *pdev) return 0; err_disable_shm_cache: - optee_disable_shm_cache(optee); + if (!optee->rpc_param_count) + optee_disable_shm_cache(optee); optee_smc_notif_uninit_irq(optee); optee_unregister_devices(); err_notif_uninit: