Hi Maxime, On Fri, 2024-06-21 at 11:00 +0200, mripard@xxxxxxxxxx wrote: > Hi, > > On Tue, Jun 11, 2024 at 09:13:03AM GMT, Jason-JH Lin (林睿祥) wrote: > > Hi Maxime, > > [snip] > > I have changed user space to use DMA_HEAP_IOCTL_ALLOC to allocate > > secure buffer, but I still encounter the problem of determining > > whether > > the buffer is secure in mediatek-drm driver to add some secure > > configure for hardware. > > > > > > As the comment in [1], dma driver won't provide API for use. > > [1]: > > https://patchwork.kernel.org/project/linux-mediatek/patch/20240515112308.10171-3-yong.wu@xxxxxxxxxxxx/#25857255 > > > > > > So I use name checking at [PATCH v6 3/7] like this currently: > > > > struct drm_gem_object *mtk_gem_prime_import_sg_table(struct > > drm_device > > *dev, > > struct dma_buf_attachment *attach, struct sg_table *sg) > > { > > struct mtk_gem_obj *mtk_gem; > > > > /* check if the entries in the sg_table are contiguous */ > > if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) { > > DRM_ERROR("sg_table is not contiguous"); > > return ERR_PTR(-EINVAL); > > } > > > > mtk_gem = mtk_gem_init(dev, attach->dmabuf->size); > > if (IS_ERR(mtk_gem)) > > return ERR_CAST(mtk_gem); > > > > + mtk_gem->secure = (!strncmp(attach->dmabuf->exp_name, > > "restricted", > > 10)); > > mtk_gem->dma_addr = sg_dma_address(sg->sgl); > > + mtk_gem->size = attach->dmabuf->size; > > mtk_gem->sg = sg; > > > > return &mtk_gem->base; > > } > > > > But I want to change this name checking to the information brought > > from > > user space. > > I tried to use arg->flags to append the secure flag in user space > > and > > call drmPrimeHandleToFD() to pass it to DRM driver, but it will be > > blocked by at the beginning of the drm_prime_handle_to_fd_ioctl(). > > I agree with you, it's something to discuss mostly with the dma-buf > maintainers but it would be better to just set a flag on the dma-buf, > and use that flag whenever necessary. > > It might be related to the recent work I did to introduce allocation > flags too: > https://lore.kernel.org/linux-media/20240515-dma-buf-ecc-heap-v1-0-54cbbd049511@xxxxxxxxxx/ > Thanks for your information! I'll discuss with dma-buf maintainer in series [1]. Regards, Jason-JH Lin > Maxime
