[Linaro-mm-sig] Re: [PATCH v2 7/8] dma_buf: heaps: secure_heap: Add a new MediaTek CMA heap

Most of the things in this patch should go in the MTK specific implementation (except for the secure_heap_init changes). Especially the RESERVEDMEM_OF_DECLARE.

On Sat, Nov 11, 2023 at 3:18 AM Yong Wu yong.wu@mediatek.com wrote:

Create a new MediaTek CMA heap from the CMA reserved buffer.

In this heap, When the first allocating buffer, use cma_alloc to prepare whole the CMA range, then send its range to TEE to protect and manage. For the later allocating, we just adds the cma_used_size_mtk.

This CMA flow may be different with the normal CMA heap of next patch. So I named the variable with _mtk suffix like cma_page_mtk/ cma_used_size_mtk. This is also to distinguish it from the cma_page of the buffer structure in the next patch.

When SVP done, cma_release will release the buffer, then kernel may reuse it.

Meanwhile, this patch adds a "heap_init" pointer, while allows some heap initialization operations. This case also checks if the CMA range is ready.

Signed-off-by: Yong Wu yong.wu@mediatek.com

drivers/dma-buf/heaps/secure_heap.c | 124 +++++++++++++++++++++++++++- 1 file changed, 122 insertions(+), 2 deletions(-)

diff --git a/drivers/dma-buf/heaps/secure_heap.c b/drivers/dma-buf/heaps/secure_heap.c index 25cc95442c56..f8b84fd16288 100644 --- a/drivers/dma-buf/heaps/secure_heap.c +++ b/drivers/dma-buf/heaps/secure_heap.c @@ -4,11 +4,12 @@

• Copyright (C) 2023 MediaTek Inc.

*/

+#include <linux/cma.h> #include <linux/dma-buf.h> #include <linux/dma-heap.h> #include <linux/err.h> #include <linux/module.h> +#include <linux/of_reserved_mem.h> #include <linux/scatterlist.h> #include <linux/slab.h> #include <linux/tee_drv.h> @@ -25,6 +26,8 @@ enum secure_buffer_tee_cmd { /* PARAM NUM always is 4. */ * [in] value[0].a: The buffer size. * value[0].b: alignment. * [in] value[1].a: enum secure_memory_type.

•    * [in]  value[2].a: pa base in cma case.
  

•    *       value[2].b: The buffer size in cma case.
     * [out] value[3].a: The secure handle.
     */
    TZCMD_SECMEM_ZALLOC = 0,
  

@@ -45,6 +48,13 @@ enum secure_memory_type { * management is inside the TEE. */ SECURE_MEMORY_TYPE_MTK_CM_TZ = 1,

•   /*
  

•    * MediaTek dynamic chunk memory carved out from CMA.
  

•    * In normal case, the CMA could be used in kernel; When SVP start, we will
  

•    * allocate whole this CMA and pass whole the CMA PA and size into TEE to
  

•    * protect it, then the detail memory management also is inside the TEE.
  

•    */
  

•   SECURE_MEMORY_TYPE_MTK_CM_CMA   = 2,
  

};

struct secure_buffer { @@ -70,6 +80,7 @@ struct secure_heap_prv_data { */ const int tee_command_id_base;

•   int     (*heap_init)(struct secure_heap *sec_heap);
    int     (*memory_alloc)(struct secure_heap *sec_heap, struct secure_buffer *sec_buf);
    void    (*memory_free)(struct secure_heap *sec_heap, struct secure_buffer *sec_buf);
  
  

@@ -86,6 +97,13 @@ struct secure_heap { u32 tee_session;

    const struct secure_heap_prv_data *data;

•   struct cma              *cma;
  

•   struct page             *cma_page_mtk;
  

•   unsigned long           cma_paddr;
  

•   unsigned long           cma_size;
  

•   unsigned long           cma_used_size_mtk;
  

•   struct mutex            lock; /* lock for cma_used_size_mtk */
  

};

struct secure_heap_attachment { @@ -168,7 +186,10 @@ static int secure_heap_tee_secure_memory(struct secure_heap *sec_heap, params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT; params[1].u.value.a = sec_heap->mem_type; params[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;

•   if (sec_heap->cma && sec_heap->mem_type == SECURE_MEMORY_TYPE_MTK_CM_CMA) {
  

•           params[2].u.value.a = sec_heap->cma_paddr;
  

•           params[2].u.value.b = sec_heap->cma_size;
  

•   }
    params[3].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
    ret = secure_heap_tee_service_call(sec_heap->tee_ctx, sec_heap->tee_session,
                                       data->tee_command_id_base + TZCMD_SECMEM_ZALLOC,
  

@@ -197,6 +218,66 @@ static void secure_heap_tee_unsecure_memory(struct secure_heap *sec_heap, sec_heap->name, sec_buf->sec_handle, params[1].u.value.a); }

+static int mtk_secure_memory_cma_allocate(struct secure_heap *sec_heap,

•                                     struct secure_buffer *sec_buf)
  

+{

•   /*
  

•    * Allocate CMA only when allocating buffer for the first time, and just
  

•    * increase cma_used_size_mtk at the other time.
  

•    */
  

•   mutex_lock(&sec_heap->lock);
  

•   if (sec_heap->cma_used_size_mtk)
  

•           goto add_size;
  

•   mutex_unlock(&sec_heap->lock);
  

•   sec_heap->cma_page_mtk = cma_alloc(sec_heap->cma, sec_heap->cma_size >> PAGE_SHIFT,
  

•                                      get_order(PAGE_SIZE), false);
  

•   if (!sec_heap->cma_page_mtk)
  

•           return -ENOMEM;
  

•   mutex_lock(&sec_heap->lock);
  

+add_size:

•   sec_heap->cma_used_size_mtk += sec_buf->size;
  

•   mutex_unlock(&sec_heap->lock);
  

•   return 0;
  

+}

+static void mtk_secure_memory_cma_free(struct secure_heap *sec_heap,

•                                  struct secure_buffer *sec_buf)
  

+{

•   bool cma_is_empty;
  

•   mutex_lock(&sec_heap->lock);
  

•   sec_heap->cma_used_size_mtk -= sec_buf->size;
  

•   cma_is_empty = !sec_heap->cma_used_size_mtk;
  

•   mutex_unlock(&sec_heap->lock);
  

•   if (cma_is_empty)
  

•           cma_release(sec_heap->cma, sec_heap->cma_page_mtk,
  

•                       sec_heap->cma_size >> PAGE_SHIFT);
  

+}

+static int mtk_secure_heap_cma_init(struct secure_heap *sec_heap) +{

•   if (!sec_heap->cma)
  

•           return -EINVAL;
  

•   mutex_init(&sec_heap->lock);
  

•   return 0;
  

+}

+/* Use CMA to prepare the buffer and the memory allocating is within the TEE. */ +const struct secure_heap_prv_data mtk_sec_mem_data_cma = {

•   .uuid                   = TZ_TA_MEM_UUID_MTK,
  

•   .tee_impl_id            = TEE_IMPL_ID_OPTEE,
  

•   .tee_command_id_base    = TEE_MEM_COMMAND_ID_BASE_MTK,
  

•   .heap_init              = mtk_secure_heap_cma_init,
  

•   .memory_alloc           = mtk_secure_memory_cma_allocate,
  

•   .memory_free            = mtk_secure_memory_cma_free,
  

•   .secure_the_memory      = secure_heap_tee_secure_memory,
  

•   .unsecure_the_memory    = secure_heap_tee_unsecure_memory,
  

+};

/* The memory allocating is within the TEE. */ const struct secure_heap_prv_data mtk_sec_mem_data = { .uuid = TZ_TA_MEM_UUID_MTK, @@ -420,20 +501,59 @@ static struct secure_heap secure_heaps[] = { .mem_type = SECURE_MEMORY_TYPE_MTK_CM_TZ, .data = &mtk_sec_mem_data, },

•   {
  

•           .name           = "secure_mtk_cma",
  

•           .mem_type       = SECURE_MEMORY_TYPE_MTK_CM_CMA,
  

•           .data           = &mtk_sec_mem_data_cma,
  

•   },
  

};

+static int __init secure_cma_init(struct reserved_mem *rmem) +{

•   struct secure_heap *sec_heap = secure_heaps;
  

•   struct cma *sec_cma;
  

•   int ret, i;
  

•   ret = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name,
  

•                               &sec_cma);
  

•   if (ret) {
  

•           pr_err("%s: %s set up CMA fail\n", __func__, rmem->name);
  

•           return ret;
  

•   }
  

•   for (i = 0; i < ARRAY_SIZE(secure_heaps); i++, sec_heap++) {
  

•           if (sec_heap->mem_type != SECURE_MEMORY_TYPE_MTK_CM_CMA)
  

•                   continue;
  

•           sec_heap->cma = sec_cma;
  

•           sec_heap->cma_paddr = rmem->base;
  

•           sec_heap->cma_size = rmem->size;
  

•   }
  

•   return 0;
  

+}

+RESERVEDMEM_OF_DECLARE(secure_cma, "secure_cma_region", secure_cma_init);

static int secure_heap_init(void) { struct secure_heap *sec_heap = secure_heaps; struct dma_heap_export_info exp_info; struct dma_heap *heap; unsigned int i;

•   int ret;
  
    for (i = 0; i < ARRAY_SIZE(secure_heaps); i++, sec_heap++) {
            exp_info.name = sec_heap->name;
            exp_info.ops = &sec_heap_ops;
            exp_info.priv = (void *)sec_heap;
  
  

•           if (sec_heap->data && sec_heap->data->heap_init) {
  

•                   ret = sec_heap->data->heap_init(sec_heap);
  

•                   if (ret) {
  

•                           pr_err("sec_heap %s init fail %d.\n", sec_heap->name, ret);
  

•                           continue;
  

•                   }
  

•           }
            heap = dma_heap_add(&exp_info);
            if (IS_ERR(heap))
                    return PTR_ERR(heap);
  

-- 2.25.1