2023-10-19 04:46:50

by Vijayanand Jitta

[permalink] [raw]
Subject: Re: [PATCH 6/9] dma-buf: heaps: mtk_sec_heap: Add tee service call for buffer allocating/freeing



On 9/11/2023 8:00 AM, Yong Wu wrote:
> Add TEE service call for secure memory allocating/freeing.
>
> Signed-off-by: Anan Sun <[email protected]>
> Signed-off-by: Yong Wu <[email protected]>
> ---
> drivers/dma-buf/heaps/mtk_secure_heap.c | 69 ++++++++++++++++++++++++-
> 1 file changed, 68 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-buf/heaps/mtk_secure_heap.c
> index e3da33a3d083..14c2a16a7164 100644
> --- a/drivers/dma-buf/heaps/mtk_secure_heap.c
> +++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
> @@ -17,6 +17,9 @@
>
> #define MTK_TEE_PARAM_NUM 4
>
> +#define TZCMD_MEM_SECURECM_UNREF 7
> +#define TZCMD_MEM_SECURECM_ZALLOC 15
> +
> /*
> * MediaTek secure (chunk) memory type
> *
> @@ -29,6 +32,8 @@ enum kree_mem_type {
> struct mtk_secure_heap_buffer {
> struct dma_heap *heap;
> size_t size;
> +
> + u32 sec_handle;
> };
>
> struct mtk_secure_heap {
> @@ -80,6 +85,63 @@ static int mtk_kree_secure_session_init(struct mtk_secure_heap *sec_heap)
> return ret;
> }
>
> +static int
> +mtk_sec_mem_tee_service_call(struct tee_context *tee_ctx, u32 session,
> + unsigned int command, struct tee_param *params)
> +{
> + struct tee_ioctl_invoke_arg arg = {0};
> + int ret;
> +
> + arg.num_params = MTK_TEE_PARAM_NUM;
> + arg.session = session;
> + arg.func = command;
> +
> + ret = tee_client_invoke_func(tee_ctx, &arg, params);
> + if (ret < 0 || arg.ret) {
> + pr_err("%s: cmd %d ret %d:%x.\n", __func__, command, ret, arg.ret);
> + ret = -EOPNOTSUPP;
> + }
> + return ret;
> +}
> +
> +static int mtk_sec_mem_allocate(struct mtk_secure_heap *sec_heap,
> + struct mtk_secure_heap_buffer *sec_buf)
> +{
> + struct tee_param params[MTK_TEE_PARAM_NUM] = {0};
> + u32 mem_session = sec_heap->mem_session;
> + int ret;
> +
> + params[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
> + params[0].u.value.a = SZ_4K; /* alignment */
> + params[0].u.value.b = sec_heap->mem_type; /* memory type */
> + params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
> + params[1].u.value.a = sec_buf->size;
> + params[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
> +
> + /* Always request zeroed buffer */
> + ret = mtk_sec_mem_tee_service_call(sec_heap->tee_ctx, mem_session,
> + TZCMD_MEM_SECURECM_ZALLOC, params);

I see here optee calls are being used to secure memory.

For a secure heap, there can be multiple ways on how we want to secure memory,
for eg : by using qcom_scm_assign_mem.

This interface restricts securing memory to only optee calls.
can we have a way to choose ops that we want to secure memory ?

Thanks,
Vijay

> + if (ret)
> + return -ENOMEM;
> +
> + sec_buf->sec_handle = params[2].u.value.a;
> + return 0;
> +}
> +
> +static void mtk_sec_mem_release(struct mtk_secure_heap *sec_heap,
> + struct mtk_secure_heap_buffer *sec_buf)
> +{
> + struct tee_param params[MTK_TEE_PARAM_NUM] = {0};
> + u32 mem_session = sec_heap->mem_session;
> +
> + params[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
> + params[0].u.value.a = sec_buf->sec_handle;
> + params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
> +
> + mtk_sec_mem_tee_service_call(sec_heap->tee_ctx, mem_session,
> + TZCMD_MEM_SECURECM_UNREF, params);
> +}
> +
> static struct dma_buf *
> mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
> unsigned long fd_flags, unsigned long heap_flags)
> @@ -107,6 +169,9 @@ mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
> sec_buf->size = size;
> sec_buf->heap = heap;
>
> + ret = mtk_sec_mem_allocate(sec_heap, sec_buf);
> + if (ret)
> + goto err_free_buf;
> exp_info.exp_name = dma_heap_get_name(heap);
> exp_info.size = sec_buf->size;
> exp_info.flags = fd_flags;
> @@ -115,11 +180,13 @@ mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
> dmabuf = dma_buf_export(&exp_info);
> if (IS_ERR(dmabuf)) {
> ret = PTR_ERR(dmabuf);
> - goto err_free_buf;
> + goto err_free_sec_mem;
> }
>
> return dmabuf;
>
> +err_free_sec_mem:
> + mtk_sec_mem_release(sec_heap, sec_buf);
> err_free_buf:
> kfree(sec_buf);
> return ERR_PTR(ret);


2023-10-20 10:02:48

by Yong Wu (吴勇)

[permalink] [raw]
Subject: Re: [PATCH 6/9] dma-buf: heaps: mtk_sec_heap: Add tee service call for buffer allocating/freeing

Hi Vijayanand,

Thanks very much for your review.

On Thu, 2023-10-19 at 10:15 +0530, Vijayanand Jitta wrote:
>
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>
>
> On 9/11/2023 8:00 AM, Yong Wu wrote:
> > Add TEE service call for secure memory allocating/freeing.
> >
> > Signed-off-by: Anan Sun <[email protected]>
> > Signed-off-by: Yong Wu <[email protected]>
> > ---
> > drivers/dma-buf/heaps/mtk_secure_heap.c | 69
> ++++++++++++++++++++++++-
> > 1 file changed, 68 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-
> buf/heaps/mtk_secure_heap.c
> > index e3da33a3d083..14c2a16a7164 100644
> > --- a/drivers/dma-buf/heaps/mtk_secure_heap.c
> > +++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
> > @@ -17,6 +17,9 @@
> >
> > #define MTK_TEE_PARAM_NUM4
> >
> > +#define TZCMD_MEM_SECURECM_UNREF7
> > +#define TZCMD_MEM_SECURECM_ZALLOC15
> > +
> > /*
> > * MediaTek secure (chunk) memory type
> > *
> > @@ -29,6 +32,8 @@ enum kree_mem_type {
> > struct mtk_secure_heap_buffer {
> > struct dma_heap*heap;
> > size_tsize;
> > +
> > +u32sec_handle;
> > };
> >
> > struct mtk_secure_heap {
> > @@ -80,6 +85,63 @@ static int mtk_kree_secure_session_init(struct
> mtk_secure_heap *sec_heap)
> > return ret;
> > }
> >
> > +static int
> > +mtk_sec_mem_tee_service_call(struct tee_context *tee_ctx, u32
> session,
> > + unsigned int command, struct tee_param *params)
> > +{
> > +struct tee_ioctl_invoke_arg arg = {0};
> > +int ret;
> > +
> > +arg.num_params = MTK_TEE_PARAM_NUM;
> > +arg.session = session;
> > +arg.func = command;
> > +
> > +ret = tee_client_invoke_func(tee_ctx, &arg, params);
> > +if (ret < 0 || arg.ret) {
> > +pr_err("%s: cmd %d ret %d:%x.\n", __func__, command, ret,
> arg.ret);
> > +ret = -EOPNOTSUPP;
> > +}
> > +return ret;
> > +}
> > +
> > +static int mtk_sec_mem_allocate(struct mtk_secure_heap *sec_heap,
> > +struct mtk_secure_heap_buffer *sec_buf)
> > +{
> > +struct tee_param params[MTK_TEE_PARAM_NUM] = {0};
> > +u32 mem_session = sec_heap->mem_session;
> > +int ret;
> > +
> > +params[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
> > +params[0].u.value.a = SZ_4K;/* alignment */
> > +params[0].u.value.b = sec_heap->mem_type;/* memory type */
> > +params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
> > +params[1].u.value.a = sec_buf->size;
> > +params[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
> > +
> > +/* Always request zeroed buffer */
> > +ret = mtk_sec_mem_tee_service_call(sec_heap->tee_ctx, mem_session,
> > + TZCMD_MEM_SECURECM_ZALLOC, params);
>
> I see here optee calls are being used to secure memory.
>
> For a secure heap, there can be multiple ways on how we want to
> secure memory,
> for eg : by using qcom_scm_assign_mem.
>
> This interface restricts securing memory to only optee calls.
> can we have a way to choose ops that we want to secure memory ?

Thanks for this suggestion. So it looks like there are four operations
in the abstract ops. Something like this?

struct sec_memory_ops {
int (*sec_memory_init)() //we need initialise tee session here.
int (*sec_memory_alloc)()
int (*sec_memory_free)()
void (*sec_memory_uninit)()
}

Do you also need tee operation like tee_client_open_session and
tee_client_invoke_func?
if so, your UUID and TEE command ID value are also different, right?

We may also need new macros on how to choose different sec_memory_ops
since we don't have different bindings.

>
> Thanks,
> Vijay