[PATCH 2/2] dma-buf: heaps: secure_heap: Add qcom secure system heap

From: Pratyush Brahma
Date: Wed Nov 22 2023 - 08:48:38 EST


From: Vijayanand Jitta <quic_vjitta@xxxxxxxxxxx>

Add secure system for Pixel and Non pixel video usecases, this
allocates from system heap and secures using qcom_scm_aasign_mem.

Change-Id: If0702f85bff651843c6a5c83694043364229e66b
Signed-off-by: Vijayanand Jitta <quic_vjitta@xxxxxxxxxxx>
---
drivers/dma-buf/heaps/secure_heap.c | 163 +++++++++++++++++++++++++++-
1 file changed, 160 insertions(+), 3 deletions(-)

diff --git a/drivers/dma-buf/heaps/secure_heap.c b/drivers/dma-buf/heaps/secure_heap.c
index 04e2ee000e19..cdcf4b3f5333 100644
--- a/drivers/dma-buf/heaps/secure_heap.c
+++ b/drivers/dma-buf/heaps/secure_heap.c
@@ -58,6 +58,11 @@ enum secure_memory_type {
* protect it, then the detail memory management also is inside the TEE.
*/
SECURE_MEMORY_TYPE_MTK_CM_CMA = 2,
+ /*
+ * QCOM secure system heap, use system heap to alloc/free.
+ * and use qcom_scm_assign_mem to secure the memory.
+ */
+ SECURE_MEMORY_TYPE_QCOM_SYSTEM = 3,
};

struct secure_buffer {
@@ -69,6 +74,7 @@ struct secure_buffer {
*/
u32 sec_handle;
struct page *cma_page;
+ struct sg_table sg_table;
};

#define TEE_MEM_COMMAND_ID_BASE_MTK 0x10000
@@ -329,11 +335,26 @@ static int secure_heap_qcom_secure_memory(struct secure_heap *sec_heap,
next[0].vmid = data->vmid;
next[0].perm = data->perm;

-
- ret = qcom_scm_assign_mem(page_to_phys(sec_buf->cma_page),
+ if (sec_heap->mem_type == SECURE_MEMORY_TYPE_CMA) {
+ ret = qcom_scm_assign_mem(page_to_phys(sec_buf->cma_page),
sec_buf->size, &src_perms,
next, 1);
+ } else if (sec_heap->mem_type == SECURE_MEMORY_TYPE_QCOM_SYSTEM) {
+ struct sg_table *table;
+ struct scatterlist *sg;
+ int i = 0;
+
+ table = &sec_buf->sg_table;
+ for_each_sgtable_sg(table, sg, i) {
+ struct page *page = sg_page(sg);

+ ret = qcom_scm_assign_mem(page_to_phys(page),
+ page_size(page), &src_perms,
+ next, 1);
+ if (ret)
+ break;
+ }
+ }
return ret;
}

@@ -347,9 +368,24 @@ static void secure_heap_qcom_unsecure_memory(struct secure_heap *sec_heap,
next[0].vmid = QCOM_SCM_VMID_HLOS;
next[0].perm = QCOM_SCM_PERM_RWX;

- qcom_scm_assign_mem(page_to_phys(sec_buf->cma_page),
+ if (sec_heap->mem_type == SECURE_MEMORY_TYPE_CMA) {
+ qcom_scm_assign_mem(page_to_phys(sec_buf->cma_page),
sec_buf->size, &src_perms,
next, 1);
+ } else if (sec_heap->mem_type == SECURE_MEMORY_TYPE_QCOM_SYSTEM) {
+ struct sg_table *table;
+ struct scatterlist *sg;
+ int i = 0;
+
+ table = &sec_buf->sg_table;
+ for_each_sgtable_sg(table, sg, i) {
+ struct page *page = sg_page(sg);
+
+ qcom_scm_assign_mem(page_to_phys(page),
+ page_size(page), &src_perms,
+ next, 1);
+ }
+ }
}

const struct secure_heap_prv_data qcom_cma_sec_mem_data = {
@@ -361,6 +397,117 @@ const struct secure_heap_prv_data qcom_cma_sec_mem_data = {
.unsecure_the_memory = secure_heap_qcom_unsecure_memory,
};

+/* Using system heap allocator */
+#define LOW_ORDER_GFP (GFP_HIGHUSER | __GFP_ZERO)
+#define HIGH_ORDER_GFP (((GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN \
+ | __GFP_NORETRY) & ~__GFP_RECLAIM) \
+ | __GFP_COMP)
+static gfp_t order_flags[] = {HIGH_ORDER_GFP, HIGH_ORDER_GFP, LOW_ORDER_GFP};
+static const unsigned int orders[] = {8, 4, 0};
+#define NUM_ORDERS ARRAY_SIZE(orders)
+
+static struct page *alloc_largest_available(unsigned long size,
+ unsigned int max_order)
+{
+ struct page *page;
+ int i;
+
+ for (i = 0; i < NUM_ORDERS; i++) {
+ if (size < (PAGE_SIZE << orders[i]))
+ continue;
+ if (max_order < orders[i])
+ continue;
+
+ page = alloc_pages(order_flags[i], orders[i]);
+ if (!page)
+ continue;
+ return page;
+ }
+ return NULL;
+}
+
+static int qcom_system_secure_memory_allocate(struct secure_heap *sec_heap,
+ struct secure_buffer *sec_buf)
+{
+ unsigned long size_remaining = sec_buf->size;
+ unsigned int max_order = orders[0];
+ struct sg_table *table;
+ struct scatterlist *sg;
+ struct list_head pages;
+ struct page *page, *tmp_page;
+ int i = 0, ret = -ENOMEM;
+
+ INIT_LIST_HEAD(&pages);
+ while (size_remaining > 0) {
+ /*
+ * Avoid trying to allocate memory if the process
+ * has been killed by SIGKILL
+ */
+ if (fatal_signal_pending(current)) {
+ return -EINTR;
+ }
+
+ page = alloc_largest_available(size_remaining, max_order);
+ if (!page)
+ goto free;
+
+ list_add_tail(&page->lru, &pages);
+ size_remaining -= page_size(page);
+ max_order = compound_order(page);
+ i++;
+ }
+ table = &sec_buf->sg_table;
+ if (sg_alloc_table(table, i, GFP_KERNEL))
+ goto free;
+
+ sg = table->sgl;
+ list_for_each_entry_safe(page, tmp_page, &pages, lru) {
+ sg_set_page(sg, page, page_size(page), 0);
+ sg = sg_next(sg);
+ list_del(&page->lru);
+ }
+ return 0;
+free:
+ list_for_each_entry_safe(page, tmp_page, &pages, lru)
+ __free_pages(page, compound_order(page));
+
+ return ret;
+}
+
+static void qcom_system_secure_memory_free(struct secure_heap *sec_heap,
+ struct secure_buffer *sec_buf)
+{
+ struct sg_table *table;
+ struct scatterlist *sg;
+ int i;
+
+ table = &sec_buf->sg_table;
+ for_each_sgtable_sg(table, sg, i) {
+ struct page *page = sg_page(sg);
+
+ __free_pages(page, compound_order(page));
+ }
+ sg_free_table(table);
+}
+
+const struct secure_heap_prv_data qcom_system_pixel_sec_mem_data = {
+ .vmid = QCOM_SCM_VMID_CP_PIXEL,
+ .perm = QCOM_SCM_PERM_RW,
+ .memory_alloc = qcom_system_secure_memory_allocate,
+ .memory_free = qcom_system_secure_memory_free,
+ .secure_the_memory = secure_heap_qcom_secure_memory,
+ .unsecure_the_memory = secure_heap_qcom_unsecure_memory,
+};
+
+const struct secure_heap_prv_data qcom_system_non_pixel_sec_mem_data = {
+ .vmid = QCOM_SCM_VMID_CP_NON_PIXEL,
+ .perm = QCOM_SCM_PERM_RW,
+ .memory_alloc = qcom_system_secure_memory_allocate,
+ .memory_free = qcom_system_secure_memory_free,
+ .secure_the_memory = secure_heap_qcom_secure_memory,
+ .unsecure_the_memory = secure_heap_qcom_unsecure_memory,
+};
+
static int secure_heap_secure_memory_allocate(struct secure_heap *sec_heap,
struct secure_buffer *sec_buf)
{
@@ -585,6 +732,16 @@ static struct secure_heap secure_heaps[] = {
.mem_type = SECURE_MEMORY_TYPE_MTK_CM_CMA,
.data = &mtk_sec_mem_data_cma,
},
+ {
+ .name = "secure_system_pixel",
+ .mem_type = SECURE_MEMORY_TYPE_QCOM_SYSTEM,
+ .data = &qcom_system_pixel_sec_mem_data,
+ },
+ {
+ .name = "secure_system_non_pixel",
+ .mem_type = SECURE_MEMORY_TYPE_QCOM_SYSTEM,
+ .data = &qcom_system_non_pixel_sec_mem_data,
+ },
};

static int __init secure_cma_init(struct reserved_mem *rmem)
--
2.34.1