[PATCH v2 8/8] dma-buf: heaps: secure_heap: Add normal CMA heap

Yong Wu
2023-11-11T11:18:17Z

Add a normal CMA heap which use the standard cma allocate.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
Hi Vijay and Jaskaran,

For this heap,
1) It uses sec_heap_buf_ops currently. I guess we cann't use the
cma_heap_buf_ops. since if it is secure buffer, some operations such
as mmap should not be allowed.
2) I didn't add how to protect/secure the buffer.

Please feel free to change to meet your requirements.
Thanks.
---
drivers/dma-buf/heaps/secure_heap.c | 38 ++++++++++++++++++++++++++++-
1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/dma-buf/heaps/secure_heap.c b/drivers/dma-buf/heaps/secure_heap.c
index f8b84fd16288..8989ad5d03e9 100644
--- a/drivers/dma-buf/heaps/secure_heap.c
+++ b/drivers/dma-buf/heaps/secure_heap.c
@@ -43,6 +43,8 @@ enum secure_buffer_tee_cmd { /* PARAM NUM always is 4. */
};

enum secure_memory_type {
+ /* CMA for the secure memory, Use the normal cma ops to alloc/free. */
+ SECURE_MEMORY_TYPE_CMA = 0,
/*
* MediaTek static chunk memory carved out for TrustZone. The memory
* management is inside the TEE.
@@ -65,6 +67,7 @@ struct secure_buffer {
* a value got from TEE.
*/
u32 sec_handle;
+ struct page *cma_page;
};

#define TEE_MEM_COMMAND_ID_BASE_MTK 0x10000
@@ -287,6 +290,33 @@ const struct secure_heap_prv_data mtk_sec_mem_data = {
.unsecure_the_memory = secure_heap_tee_unsecure_memory,
};

+static int cma_secure_memory_allocate(struct secure_heap *sec_heap,
+ struct secure_buffer *sec_buf)
+{
+ if (!sec_heap->cma)
+ return -EINVAL;
+
+ sec_buf->cma_page = cma_alloc(sec_heap->cma, sec_buf->size >> PAGE_SHIFT,
+ get_order(PAGE_SIZE), false);
+ if (!sec_buf->cma_page)
+ return -ENOMEM;
+
+ memset(page_address(sec_buf->cma_page), 0, sec_buf->size);
+ return 0;
+}
+
+static void cma_secure_memory_free(struct secure_heap *sec_heap,
+ struct secure_buffer *sec_buf)
+{
+ cma_release(sec_heap->cma, sec_buf->cma_page, sec_buf->size >> PAGE_SHIFT);
+}
+
+const struct secure_heap_prv_data cma_sec_mem_data = {
+ .memory_alloc = cma_secure_memory_allocate,
+ .memory_free = cma_secure_memory_free,
+ /* TODO : secure the buffer. */
+};
+
static int secure_heap_secure_memory_allocate(struct secure_heap *sec_heap,
struct secure_buffer *sec_buf)
{
@@ -496,6 +526,11 @@ static const struct dma_heap_ops sec_heap_ops = {
};

static struct secure_heap secure_heaps[] = {
+ {
+ .name = "secure_cma",
+ .mem_type = SECURE_MEMORY_TYPE_CMA,
+ .data = &cma_sec_mem_data,
+ },
{
.name = "secure_mtk_cm",
.mem_type = SECURE_MEMORY_TYPE_MTK_CM_TZ,
@@ -522,7 +557,8 @@ static int __init secure_cma_init(struct reserved_mem *rmem)
}

for (i = 0; i < ARRAY_SIZE(secure_heaps); i++, sec_heap++) {
- if (sec_heap->mem_type != SECURE_MEMORY_TYPE_MTK_CM_CMA)
+ if (sec_heap->mem_type != SECURE_MEMORY_TYPE_MTK_CM_CMA &&
+ sec_heap->mem_type != SECURE_MEMORY_TYPE_CMA)
continue;

sec_heap->cma = sec_cma;
--
2.25.1