On Mon, May 26, 2025 at 11:33 AM Sumit Garg sumit.garg@kernel.org wrote:
On Mon, May 26, 2025 at 11:21:47AM +0200, Jens Wiklander wrote:
On Mon, May 26, 2025 at 9:22 AM Sumit Garg sumit.garg@kernel.org wrote:
On Tue, May 20, 2025 at 05:16:49PM +0200, Jens Wiklander wrote:
Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to identify it as DMA memory. The allocated memory will later be lent to the TEE to be used as protected memory.
Signed-off-by: Jens Wiklander jens.wiklander@linaro.org
drivers/tee/tee_shm.c | 74 ++++++++++++++++++++++++++++++++++++++-- include/linux/tee_core.h | 5 +++ 2 files changed, 77 insertions(+), 2 deletions(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index e1ed52ee0a16..92a6a35e1a1e 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -5,6 +5,8 @@ #include <linux/anon_inodes.h> #include <linux/device.h> #include <linux/dma-buf.h> +#include <linux/dma-mapping.h> +#include <linux/highmem.h> #include <linux/idr.h> #include <linux/io.h> #include <linux/mm.h> @@ -13,9 +15,14 @@ #include <linux/tee_core.h> #include <linux/uaccess.h> #include <linux/uio.h> -#include <linux/highmem.h> #include "tee_private.h"
+struct tee_shm_dma_mem {
struct tee_shm shm;dma_addr_t dma_addr;struct page *page;+};
static void shm_put_kernel_pages(struct page **pages, size_t page_count) { size_t n; @@ -49,7 +56,14 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm) struct tee_shm *parent_shm = NULL; void *p = shm;
if (shm->flags & TEE_SHM_DMA_BUF) {
if (shm->flags & TEE_SHM_DMA_MEM) {struct tee_shm_dma_mem *dma_mem;dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);p = dma_mem;dma_free_pages(&teedev->dev, shm->size, dma_mem->page,dma_mem->dma_addr, DMA_BIDIRECTIONAL);Although the kernel bot already found a randconfig issue, it looks like we need to add Kconfig dependencies like HAS_DMA, DMA_CMA etc.
Also, I was thinking if we should rather add a new TEE subsystem specific Kconfig option like: TEE_DMABUF_HEAPS which can then be used to select whatever dependency is needed as well as act as a gating Kconfig for relevant features.
You mean something like this?
--- a/drivers/tee/Kconfig +++ b/drivers/tee/Kconfig @@ -13,6 +13,14 @@ menuconfig TEE
if TEE
+config TEE_DMABUF_HEAPS
booldepends on HAS_DMA && DMABUF_HEAPSYeah this looks fine to me but needs to be tested if DMA_CMA is a dependency here too.
Why? It can work without CMA for small allocations.
+config TEE_STATIC_PROTMEM_POOL
booldepends on HAS_IOMEM && TEE_DMABUF_HEAPSThe static and dynamic protected memory pools should get auto enabled if TEE_DMABUF_HEAPS is enabled since they are pre-requisite to provide the protected heaps support. Something like:
+config TEE_STATIC_PROTMEM_POOL
booldefault y if TEE_DMABUF_HEAPSdepends on HAS_IOMEM
Right, I'll update as needed.
Cheers, Jens