Add the dma_ops for this secure heap.
a) For secure buffer, cache_ops/mmap are not allowed, thus return
EPERM for them.
b) The secure buffer can't be accessed in kernel, thus it doesn't
have va/dma_address for it. Use the dma_address property to save the
"secure handle".
Signed-off-by: Anan Sun <anan.sun@xxxxxxxxxxxx>
Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
drivers/dma-buf/heaps/mtk_secure_heap.c | 116 ++++++++++++++++++++++++
1 file changed, 116 insertions(+)
diff --git a/drivers/dma-buf/heaps/mtk_secure_heap.c b/drivers/dma-buf/heaps/mtk_secure_heap.c
index 14c2a16a7164..daf6cf2121a1 100644
--- a/drivers/dma-buf/heaps/mtk_secure_heap.c
+++ b/drivers/dma-buf/heaps/mtk_secure_heap.c
@@ -9,6 +9,7 @@
#include <linux/dma-heap.h>
#include <linux/err.h>
#include <linux/module.h>
+#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/tee_drv.h>
#include <linux/uuid.h>
@@ -43,6 +44,10 @@ struct mtk_secure_heap {
struct tee_context *tee_ctx;
};
+struct mtk_secure_heap_attachment {
+ struct sg_table *table;
+};
+
static int mtk_optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
{
return ver->impl_id == TEE_IMPL_ID_OPTEE;
@@ -142,6 +147,116 @@ static void mtk_sec_mem_release(struct mtk_secure_heap *sec_heap,
TZCMD_MEM_SECURECM_UNREF, params);
}
+static int mtk_sec_heap_attach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment)
+{
+ struct mtk_secure_heap_buffer *sec_buf = dmabuf->priv;
+ struct mtk_secure_heap_attachment *a;
+ struct sg_table *table;
+ int ret = 0;
+
+ a = kzalloc(sizeof(*a), GFP_KERNEL);
+ if (!a)
+ return -ENOMEM;
+
+ table = kzalloc(sizeof(*table), GFP_KERNEL);
+ if (!table) {
+ ret = -ENOMEM;
+ goto err_free_attach;
+ }
+
+ ret = sg_alloc_table(table, 1, GFP_KERNEL);
+ if (ret)
+ goto err_free_sgt;
+ sg_set_page(table->sgl, 0, sec_buf->size, 0);
+
+ a->table = table;
+ attachment->priv = a;
+
+ return 0;
+
+err_free_sgt:
+ kfree(table);
+err_free_attach:
+ kfree(a);
+ return ret;
+}
+
+static void mtk_sec_heap_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment)
+{
+ struct mtk_secure_heap_attachment *a = attachment->priv;
+
+ sg_free_table(a->table);
+ kfree(a->table);
+ kfree(a);
+}
+
+static struct sg_table *
+mtk_sec_heap_map_dma_buf(struct dma_buf_attachment *attachment, enum dma_data_direction direction)
+{
+ struct mtk_secure_heap_attachment *a = attachment->priv;
+ struct dma_buf *dmabuf = attachment->dmabuf;
+ struct mtk_secure_heap_buffer *sec_buf = dmabuf->priv;
+ struct sg_table *table = a->table;
+
+ /*
+ * Technically dma_address refers to the address used by HW, But for secure buffer
+ * we don't know its dma_address in kernel, Instead, we only know its "secure handle".
+ * Thus use this property to save the "secure handle", and the user will use it to
+ * obtain the real address in secure world.
+ */
+ sg_dma_address(table->sgl) = sec_buf->sec_handle;
+ sg_dma_len(table->sgl) = sec_buf->size;
+
+ return table;
+}
+
+static void
+mtk_sec_heap_unmap_dma_buf(struct dma_buf_attachment *attachment, struct sg_table *table,
+ enum dma_data_direction direction)
+{
+ struct mtk_secure_heap_attachment *a = attachment->priv;
+
+ WARN_ON(a->table != table);
+ sg_dma_address(table->sgl) = 0;
+}
+
+static int
+mtk_sec_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, enum dma_data_direction direction)
+{
+ return -EPERM;
+}
+
+static int
+mtk_sec_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf, enum dma_data_direction direction)
+{
+ return -EPERM;
+}
+
+static int mtk_sec_heap_dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
+{
+ return -EPERM;
+}
+
+static void mtk_sec_heap_free(struct dma_buf *dmabuf)
+{
+ struct mtk_secure_heap_buffer *sec_buf = dmabuf->priv;
+ struct mtk_secure_heap *sec_heap = dma_heap_get_drvdata(sec_buf->heap);
+
+ mtk_sec_mem_release(sec_heap, sec_buf);
+ kfree(sec_buf);
+}
+
+static const struct dma_buf_ops mtk_sec_heap_buf_ops = {
+ .attach = mtk_sec_heap_attach,
+ .detach = mtk_sec_heap_detach,
+ .map_dma_buf = mtk_sec_heap_map_dma_buf,
+ .unmap_dma_buf = mtk_sec_heap_unmap_dma_buf,
+ .begin_cpu_access = mtk_sec_heap_dma_buf_begin_cpu_access,
+ .end_cpu_access = mtk_sec_heap_dma_buf_end_cpu_access,
+ .mmap = mtk_sec_heap_dma_buf_mmap,
+ .release = mtk_sec_heap_free,
+};
+
static struct dma_buf *
mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
unsigned long fd_flags, unsigned long heap_flags)
@@ -173,6 +288,7 @@ mtk_sec_heap_allocate(struct dma_heap *heap, size_t size,
if (ret)
goto err_free_buf;
exp_info.exp_name = dma_heap_get_name(heap);
+ exp_info.ops = &mtk_sec_heap_buf_ops;
exp_info.size = sec_buf->size;
exp_info.flags = fd_flags;
exp_info.priv = sec_buf;
--
2.25.1
