media: mtk-vcodec: Remove VA from encoder frame buffers

The encoder driver has no need to do any CPU access to the source frame
buffers. Use a separate structure for holding DMA addresses and sizes
for those and remove, so we do not end up introducing any erroneous
dereferences of those VAs.

This fixes DMA-buf import from exporters that do not provide contiguous
kernel mappings, which includes the MTK DRM driver.

Signed-off-by: Tomasz Figa <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/platform/mtk-vcodec/mtk_vcodec_enc.c

···
 	src_buf = v4l2_m2m_src_buf_remove(ctx->m2m_ctx);
 	memset(&frm_buf, 0, sizeof(frm_buf));
 	for (i = 0; i < src_buf->num_planes ; i++) {
-		frm_buf.fb_addr[i].va = vb2_plane_vaddr(src_buf, i);
 		frm_buf.fb_addr[i].dma_addr =
 				vb2_dma_contig_plane_dma_addr(src_buf, i);
 		frm_buf.fb_addr[i].size =
···
 	bs_buf.size = (size_t)dst_buf->planes[0].length;
 
 	mtk_v4l2_debug(2,
-			"Framebuf VA=%p PA=%llx Size=0x%zx;VA=%p PA=0x%llx Size=0x%zx;VA=%p PA=0x%llx Size=%zu",
-			frm_buf.fb_addr[0].va,
+			"Framebuf PA=%llx Size=0x%zx;PA=0x%llx Size=0x%zx;PA=0x%llx Size=%zu",
 			(u64)frm_buf.fb_addr[0].dma_addr,
 			frm_buf.fb_addr[0].size,
-			frm_buf.fb_addr[1].va,
 			(u64)frm_buf.fb_addr[1].dma_addr,
 			frm_buf.fb_addr[1].size,
-			frm_buf.fb_addr[2].va,
 			(u64)frm_buf.fb_addr[2].dma_addr,
 			frm_buf.fb_addr[2].size);
 

drivers/media/platform/mtk-vcodec/mtk_vcodec_util.h

···
 	dma_addr_t dma_addr;
 };
 
+struct mtk_vcodec_fb {
+	size_t size;
+	dma_addr_t dma_addr;
+};
+
 struct mtk_vcodec_ctx;
 struct mtk_vcodec_dev;
 

drivers/media/platform/mtk-vcodec/venc_drv_if.h

···
  * @fb_addr: plane frame buffer addresses
  */
 struct venc_frm_buf {
-	struct mtk_vcodec_mem fb_addr[MTK_VCODEC_MAX_PLANES];
+	struct mtk_vcodec_fb fb_addr[MTK_VCODEC_MAX_PLANES];
 };
 
 /*