Re: [PATCH 5/9] dma-buf: heaps: mtk_sec_heap: Initialise tee session

["Yong Wu (吴勇)" <Yong.Wu@mediatek.com>]

On Mon, 2023-09-11 at 11:29 +0200, AngeloGioacchino Del Regno wrote:
> Il 11/09/23 04:30, Yong Wu ha scritto:
> > The TEE probe later than dma-buf heap, and PROBE_DEDER doesn't work
> > here since this is not a platform driver, therefore initialise the
> > TEE
> > context/session while we allocate the first secure buffer.
> > 
> > Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> > ---
> >   drivers/dma-buf/heaps/mtk_secure_heap.c | 61
> > +++++++++++++++++++++++++
> >   1 file changed, 61 insertions(+)
> > 
> > diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-
> > buf/heaps/mtk_secure_heap.c
> > index bbf1c8dce23e..e3da33a3d083 100644
> > --- a/drivers/dma-buf/heaps/mtk_secure_heap.c
> > +++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
> > @@ -10,6 +10,12 @@
> >   #include <linux/err.h>
> >   #include <linux/module.h>
> >   #include <linux/slab.h>
> > +#include <linux/tee_drv.h>
> > +#include <linux/uuid.h>
> > +
> > +#define TZ_TA_MEM_UUID		"4477588a-8476-11e2-ad15-
> > e41f1390d676"
> > +
> 
> Is this UUID the same for all SoCs and all TZ versions?

Yes. It is the same for all SoCs and all TZ versions currently.

> 
> Thanks,
> Angelo
> 
> 
> > +#define MTK_TEE_PARAM_NUM		4
> >   
> >   /*
> >    * MediaTek secure (chunk) memory type
> > @@ -28,17 +34,72 @@ struct mtk_secure_heap_buffer {
> >   struct mtk_secure_heap {
> >   	const char		*name;
> >   	const enum kree_mem_type mem_type;
> > +	u32			 mem_session;
> > +	struct tee_context	*tee_ctx;
> >   };
> >   
> > +static int mtk_optee_ctx_match(struct tee_ioctl_version_data *ver,
> > const void *data)
> > +{
> > +	return ver->impl_id == TEE_IMPL_ID_OPTEE;
> > +}
> > +
> > +static int mtk_kree_secure_session_init(struct mtk_secure_heap
> > *sec_heap)
> > +{
> > +	struct tee_param t_param[MTK_TEE_PARAM_NUM] = {0};
> > +	struct tee_ioctl_open_session_arg arg = {0};
> > +	uuid_t ta_mem_uuid;
> > +	int ret;
> > +
> > +	sec_heap->tee_ctx = tee_client_open_context(NULL,
> > mtk_optee_ctx_match,
> > +						    NULL, NULL);
> > +	if (IS_ERR(sec_heap->tee_ctx)) {
> > +		pr_err("%s: open context failed, ret=%ld\n", sec_heap-
> > >name,
> > +		       PTR_ERR(sec_heap->tee_ctx));
> > +		return -ENODEV;
> > +	}
> > +
> > +	arg.num_params = MTK_TEE_PARAM_NUM;
> > +	arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
> > +	ret = uuid_parse(TZ_TA_MEM_UUID, &ta_mem_uuid);
> > +	if (ret)
> > +		goto close_context;
> > +	memcpy(&arg.uuid, &ta_mem_uuid.b, sizeof(ta_mem_uuid));
> > +
> > +	ret = tee_client_open_session(sec_heap->tee_ctx, &arg,
> > t_param);
> > +	if (ret < 0 || arg.ret) {
> > +		pr_err("%s: open session failed, ret=%d:%d\n",
> > +		       sec_heap->name, ret, arg.ret);
> > +		ret = -EINVAL;
> > +		goto close_context;
> > +	}
> > +	sec_heap->mem_session = arg.session;
> > +	return 0;
> > +
> > +close_context:
> > +	tee_client_close_context(sec_heap->tee_ctx);
> > +	return ret;
> > +}
> > +
> >   static struct dma_buf *
> >   mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
> >   		      unsigned long fd_flags, unsigned long heap_flags)
> >   {
> > +	struct mtk_secure_heap *sec_heap = dma_heap_get_drvdata(heap);
> >   	struct mtk_secure_heap_buffer *sec_buf;
> >   	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
> >   	struct dma_buf *dmabuf;
> >   	int ret;
> >   
> > +	/*
> > +	 * TEE probe may be late. Initialise the secure session in the
> > first
> > +	 * allocating secure buffer.
> > +	 */
> > +	if (!sec_heap->mem_session) {
> > +		ret = mtk_kree_secure_session_init(sec_heap);
> > +		if (ret)
> > +			return ERR_PTR(ret);
> > +	}
> > +
> >   	sec_buf = kzalloc(sizeof(*sec_buf), GFP_KERNEL);
> >   	if (!sec_buf)
> >   		return ERR_PTR(-ENOMEM);
> 
>