tee: optee: add registered buffers handling into RPC calls

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>
[jw: fix parenthesis alignment in free_pages_list()]
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
This commit is contained in:
Volodymyr Babchuk 2017-11-29 14:48:33 +02:00 committed by Jens Wiklander
parent 64cf9d8a67
commit 53a107c812
4 changed files with 102 additions and 11 deletions

View file

@ -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, &param);
optee_handle_rpc(ctx, &param, &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;
}

View file

@ -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 = {

View file

@ -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,

View file

@ -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",