Merge tag 'tee-drv-dynamic-shm-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee into next/drivers

Pull "tee dynamic shm for v4.16" from Jens Wiklander:

This pull request enables dynamic shared memory support in the TEE
subsystem as a whole and in OP-TEE in particular.

Global Platform TEE specification [1] allows client applications
to register part of own memory as a shared buffer between
application and TEE. This allows fast zero-copy communication between
TEE and REE. But current implementation of TEE in Linux does not support
this feature.

Also, current implementation of OP-TEE transport uses fixed size
pre-shared buffer for all communications with OP-TEE OS. This is okay
in the most use cases. But this prevents use of OP-TEE in virtualized
environments, because:
 a) We can't share the same buffer between different virtual machines
 b) Physically contiguous memory as seen by VM can be non-contiguous
    in reality (and as seen by OP-TEE OS) due to second stage of
    MMU translation.
 c) Size of this pre-shared buffer is limited.

So, first part of this pull request adds generic register/unregister
interface to tee subsystem. The second part adds necessary features into
OP-TEE driver, so it can use not only static pre-shared buffer, but
whole RAM to communicate with OP-TEE OS.

This change is backwards compatible allowing older secure world or
user space to work with newer kernels and vice versa.

[1] https://www.globalplatform.org/specificationsdevice.asp

* tag 'tee-drv-dynamic-shm-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: shm: inline tee_shm_get_id()
  tee: use reference counting for tee_context
  tee: optee: enable dynamic SHM support
  tee: optee: add optee-specific shared pool implementation
  tee: optee: store OP-TEE capabilities in private data
  tee: optee: add registered buffers handling into RPC calls
  tee: optee: add registered shared parameters handling
  tee: optee: add shared buffer registration functions
  tee: optee: add page list manipulation functions
  tee: optee: Update protocol definitions
  tee: shm: add page accessor functions
  tee: shm: add accessors for buffer size and page offset
  tee: add register user memory
  tee: flexible shared memory pool creation
This commit is contained in:
Arnd Bergmann
2017-12-21 17:23:52 +01:00
15 changed files with 1107 additions and 223 deletions

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",