| Message ID | 20240403102701.369-3-shawn.sung@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add mediate-drm secure flow for SVP | expand |
On Wed, Apr 03, 2024 at 06:26:54PM +0800, Shawn Sung wrote: > From: "Jason-JH.Lin" <jason-jh.lin@mediatek.com> > > Add secure buffer control flow to mtk_drm_gem. > > When user space takes DRM_MTK_GEM_CREATE_ENCRYPTED flag and size > to create a mtk_drm_gem object, mtk_drm_gem will find a matched size > dma buffer from secure dma-heap and bind it to mtk_drm_gem object. > > Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com> > Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com> > --- > drivers/gpu/drm/mediatek/mtk_gem.c | 85 +++++++++++++++++++++++++++++- > drivers/gpu/drm/mediatek/mtk_gem.h | 4 ++ > 2 files changed, 88 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_gem.c b/drivers/gpu/drm/mediatek/mtk_gem.c > index e59e0727717b7..ec34d02c14377 100644 > --- a/drivers/gpu/drm/mediatek/mtk_gem.c > +++ b/drivers/gpu/drm/mediatek/mtk_gem.c > @@ -4,6 +4,8 @@ > */ > > #include <linux/dma-buf.h> > +#include <linux/dma-heap.h> > +#include <uapi/linux/dma-heap.h> > #include <drm/mediatek_drm.h> > > #include <drm/drm.h> > @@ -102,6 +104,81 @@ struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, > return ERR_PTR(ret); > } > > +struct mtk_gem_obj *mtk_gem_create_from_heap(struct drm_device *dev, > + const char *heap, size_t size) > +{ > + struct mtk_drm_private *priv = dev->dev_private; > + struct mtk_gem_obj *mtk_gem; > + struct drm_gem_object *obj; > + struct dma_heap *dma_heap; > + struct dma_buf *dma_buf; > + struct dma_buf_attachment *attach; > + struct sg_table *sgt; > + struct iosys_map map = {}; > + int ret; > + > + mtk_gem = mtk_gem_init(dev, size); > + if (IS_ERR(mtk_gem)) > + return ERR_CAST(mtk_gem); > + > + obj = &mtk_gem->base; > + > + dma_heap = dma_heap_find(heap); > + if (!dma_heap) { > + DRM_ERROR("heap find fail\n"); > + goto err_gem_free; > + } > + dma_buf = dma_heap_buffer_alloc(dma_heap, size, > + O_RDWR | O_CLOEXEC, DMA_HEAP_VALID_HEAP_FLAGS); > + if (IS_ERR(dma_buf)) { > + DRM_ERROR("buffer alloc fail\n"); > + dma_heap_put(dma_heap); > + goto err_gem_free; > + } > + dma_heap_put(dma_heap); > + > + attach = dma_buf_attach(dma_buf, priv->dma_dev); > + if (IS_ERR(attach)) { > + DRM_ERROR("attach fail, return\n"); > + dma_buf_put(dma_buf); > + goto err_gem_free; > + } > + > + sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); > + if (IS_ERR(sgt)) { > + DRM_ERROR("map failed, detach and return\n"); > + dma_buf_detach(dma_buf, attach); > + dma_buf_put(dma_buf); > + goto err_gem_free; > + } > + obj->import_attach = attach; > + mtk_gem->dma_addr = sg_dma_address(sgt->sgl); > + mtk_gem->sg = sgt; > + mtk_gem->size = dma_buf->size; > + > + if (!strcmp(heap, "mtk_svp") || !strcmp(heap, "mtk_svp_cma")) { > + /* secure buffer can not be mapped */ > + mtk_gem->secure = true; > + } else { > + ret = dma_buf_vmap(dma_buf, &map); > + mtk_gem->kvaddr = map.vaddr; > + if (ret) { > + DRM_ERROR("map failed, ret=%d\n", ret); > + dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); > + dma_buf_detach(dma_buf, attach); > + dma_buf_put(dma_buf); > + mtk_gem->kvaddr = NULL; > + } > + } > + > + return mtk_gem; > + > +err_gem_free: > + drm_gem_object_release(obj); > + kfree(mtk_gem); > + return ERR_PTR(-ENOMEM); > +} > + > void mtk_gem_free_object(struct drm_gem_object *obj) > { > struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); > @@ -229,7 +306,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > if (IS_ERR(mtk_gem)) > return ERR_CAST(mtk_gem); > > + mtk_gem->secure = !sg_page(sg->sgl); > mtk_gem->dma_addr = sg_dma_address(sg->sgl); > + mtk_gem->size = attach->dmabuf->size; > mtk_gem->sg = sg; > > return &mtk_gem->base; > @@ -304,7 +383,11 @@ int mtk_gem_create_ioctl(struct drm_device *dev, void *data, > struct drm_mtk_gem_create *args = data; > int ret; > > - mtk_gem = mtk_gem_create(dev, args->size, false); > + if (args->flags & DRM_MTK_GEM_CREATE_ENCRYPTED) > + mtk_gem = mtk_gem_create_from_heap(dev, "mtk_svp_cma", args->size); That heap doesn't exist upstream either. Also, I'm wondering if it's the right solution there. From what I can tell, you want to allow to create encrypted buffers from the TEE. Why do we need this as a DRM ioctl at all? A heap seems like the perfect solution to do so, and then you just have to import it into DRM. I'm also not entirely sure that not having a SG list is enough to consider the buffer secure. Wouldn't a buffer allocated without a kernel mapping also be in that situation? Maxime
Hi Maxime, [snip] I'm sorry for losing your previous comment mail. I finally found a way to import this mail back so I can reply to you. > > - mtk_gem = mtk_gem_create(dev, args->size, false); > > + if (args->flags & DRM_MTK_GEM_CREATE_ENCRYPTED) > > + mtk_gem = mtk_gem_create_from_heap(dev, "mtk_svp_cma", > > args->size); > > That heap doesn't exist upstream either. Also, I'm wondering if it's > the > right solution there. > Yes, I found that its name changed to "restricted_mtk_cma" in the latest patch: https://patchwork.kernel.org/project/linux-mediatek/patch/20240515112308.10171-10-yong.wu@mediatek.com/ > From what I can tell, you want to allow to create encrypted buffers > from > the TEE. Why do we need this as a DRM ioctl at all? A heap seems like > the perfect solution to do so, and then you just have to import it > into > DRM. > OK, I'll try to change the userspace's ioctl from DRM_IOCTL_MTK_GEM_CREATE to DMA_HEAP_IOCTL_ALLOC to get the buffer fd, then import to DRM. > I'm also not entirely sure that not having a SG list is enough to > consider the buffer secure. Wouldn't a buffer allocated without a > kernel > mapping also be in that situation? > I have confirmed to Yong.Wu that secure buffer also have sg list, so the secure checking method "!sg_page(sg->sgl)" will be deprecated. Regards, Jason-JH.Lin > Maxime > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
diff --git a/drivers/gpu/drm/mediatek/mtk_gem.c b/drivers/gpu/drm/mediatek/mtk_gem.c index e59e0727717b7..ec34d02c14377 100644 --- a/drivers/gpu/drm/mediatek/mtk_gem.c +++ b/drivers/gpu/drm/mediatek/mtk_gem.c @@ -4,6 +4,8 @@ */ #include <linux/dma-buf.h> +#include <linux/dma-heap.h> +#include <uapi/linux/dma-heap.h> #include <drm/mediatek_drm.h> #include <drm/drm.h> @@ -102,6 +104,81 @@ struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, return ERR_PTR(ret); } +struct mtk_gem_obj *mtk_gem_create_from_heap(struct drm_device *dev, + const char *heap, size_t size) +{ + struct mtk_drm_private *priv = dev->dev_private; + struct mtk_gem_obj *mtk_gem; + struct drm_gem_object *obj; + struct dma_heap *dma_heap; + struct dma_buf *dma_buf; + struct dma_buf_attachment *attach; + struct sg_table *sgt; + struct iosys_map map = {}; + int ret; + + mtk_gem = mtk_gem_init(dev, size); + if (IS_ERR(mtk_gem)) + return ERR_CAST(mtk_gem); + + obj = &mtk_gem->base; + + dma_heap = dma_heap_find(heap); + if (!dma_heap) { + DRM_ERROR("heap find fail\n"); + goto err_gem_free; + } + dma_buf = dma_heap_buffer_alloc(dma_heap, size, + O_RDWR | O_CLOEXEC, DMA_HEAP_VALID_HEAP_FLAGS); + if (IS_ERR(dma_buf)) { + DRM_ERROR("buffer alloc fail\n"); + dma_heap_put(dma_heap); + goto err_gem_free; + } + dma_heap_put(dma_heap); + + attach = dma_buf_attach(dma_buf, priv->dma_dev); + if (IS_ERR(attach)) { + DRM_ERROR("attach fail, return\n"); + dma_buf_put(dma_buf); + goto err_gem_free; + } + + sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); + if (IS_ERR(sgt)) { + DRM_ERROR("map failed, detach and return\n"); + dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + goto err_gem_free; + } + obj->import_attach = attach; + mtk_gem->dma_addr = sg_dma_address(sgt->sgl); + mtk_gem->sg = sgt; + mtk_gem->size = dma_buf->size; + + if (!strcmp(heap, "mtk_svp") || !strcmp(heap, "mtk_svp_cma")) { + /* secure buffer can not be mapped */ + mtk_gem->secure = true; + } else { + ret = dma_buf_vmap(dma_buf, &map); + mtk_gem->kvaddr = map.vaddr; + if (ret) { + DRM_ERROR("map failed, ret=%d\n", ret); + dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); + dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + mtk_gem->kvaddr = NULL; + } + } + + return mtk_gem; + +err_gem_free: + drm_gem_object_release(obj); + kfree(mtk_gem); + return ERR_PTR(-ENOMEM); +} + void mtk_gem_free_object(struct drm_gem_object *obj) { struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); @@ -229,7 +306,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, if (IS_ERR(mtk_gem)) return ERR_CAST(mtk_gem); + mtk_gem->secure = !sg_page(sg->sgl); mtk_gem->dma_addr = sg_dma_address(sg->sgl); + mtk_gem->size = attach->dmabuf->size; mtk_gem->sg = sg; return &mtk_gem->base; @@ -304,7 +383,11 @@ int mtk_gem_create_ioctl(struct drm_device *dev, void *data, struct drm_mtk_gem_create *args = data; int ret; - mtk_gem = mtk_gem_create(dev, args->size, false); + if (args->flags & DRM_MTK_GEM_CREATE_ENCRYPTED) + mtk_gem = mtk_gem_create_from_heap(dev, "mtk_svp_cma", args->size); + else + mtk_gem = mtk_gem_create(dev, args->size, false); + if (IS_ERR(mtk_gem)) return PTR_ERR(mtk_gem); diff --git a/drivers/gpu/drm/mediatek/mtk_gem.h b/drivers/gpu/drm/mediatek/mtk_gem.h index 4d7598220ca8f..75cf50495abe0 100644 --- a/drivers/gpu/drm/mediatek/mtk_gem.h +++ b/drivers/gpu/drm/mediatek/mtk_gem.h @@ -27,9 +27,11 @@ struct mtk_gem_obj { void *cookie; void *kvaddr; dma_addr_t dma_addr; + size_t size; unsigned long dma_attrs; struct sg_table *sg; struct page **pages; + bool secure; }; #define to_mtk_gem_obj(x) container_of(x, struct mtk_gem_obj, base) @@ -37,6 +39,8 @@ struct mtk_gem_obj { void mtk_gem_free_object(struct drm_gem_object *gem); struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, size_t size, bool alloc_kmap); +struct mtk_gem_obj *mtk_gem_create_from_heap(struct drm_device *dev, + const char *heap, size_t size); int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, struct drm_mode_create_dumb *args); struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj);