[PATCH v5 5/9] dma-buf: heaps: restricted_heap: Add private heap ops

[Yong Wu]

Add "struct restricted_heap_ops". For the restricted memory, totally there
are two steps:
a) alloc: Allocate the buffer in kernel;
b) restrict_buf: Restrict/Protect/Secure that buffer.
The "alloc" is mandatory while "restrict_buf" is optional since it may
be part of "alloc".

Signed-off-by: Yong Wu <yong...@mediatek.com>
---
 drivers/dma-buf/heaps/restricted_heap.c | 41 ++++++++++++++++++++++++-
 drivers/dma-buf/heaps/restricted_heap.h | 12 ++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/drivers/dma-buf/heaps/restricted_heap.c 
b/drivers/dma-buf/heaps/restricted_heap.c
index c2ae19ba7d7e..8bb3c1876a69 100644
--- a/drivers/dma-buf/heaps/restricted_heap.c
+++ b/drivers/dma-buf/heaps/restricted_heap.c
@@ -12,10 +12,44 @@
 
 #include "restricted_heap.h"
 
+static int
+restricted_heap_memory_allocate(struct restricted_heap *rheap, struct 
restricted_buffer *buf)
+{
+       const struct restricted_heap_ops *ops = rheap->ops;
+       int ret;
+
+       ret = ops->alloc(rheap, buf);
+       if (ret)
+               return ret;
+
+       if (ops->restrict_buf) {
+               ret = ops->restrict_buf(rheap, buf);
+               if (ret)
+                       goto buf_free;
+       }
+       return 0;
+
+buf_free:
+       ops->free(rheap, buf);
+       return ret;
+}
+
+static void
+restricted_heap_memory_free(struct restricted_heap *rheap, struct 
restricted_buffer *buf)
+{
+       const struct restricted_heap_ops *ops = rheap->ops;
+
+       if (ops->unrestrict_buf)
+               ops->unrestrict_buf(rheap, buf);
+
+       ops->free(rheap, buf);
+}
+
 static struct dma_buf *
 restricted_heap_allocate(struct dma_heap *heap, unsigned long size,
                         unsigned long fd_flags, unsigned long heap_flags)
 {
+       struct restricted_heap *rheap = dma_heap_get_drvdata(heap);
        struct restricted_buffer *restricted_buf;
        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
        struct dma_buf *dmabuf;
@@ -28,6 +62,9 @@ restricted_heap_allocate(struct dma_heap *heap, unsigned long 
size,
        restricted_buf->size = ALIGN(size, PAGE_SIZE);
        restricted_buf->heap = heap;
 
+       ret = restricted_heap_memory_allocate(rheap, restricted_buf);
+       if (ret)
+               goto err_free_buf;
        exp_info.exp_name = dma_heap_get_name(heap);
        exp_info.size = restricted_buf->size;
        exp_info.flags = fd_flags;
@@ -36,11 +73,13 @@ restricted_heap_allocate(struct dma_heap *heap, unsigned 
long size,
        dmabuf = dma_buf_export(&exp_info);
        if (IS_ERR(dmabuf)) {
                ret = PTR_ERR(dmabuf);
-               goto err_free_buf;
+               goto err_free_rstrd_mem;
        }
 
        return dmabuf;
 
+err_free_rstrd_mem:
+       restricted_heap_memory_free(rheap, restricted_buf);
 err_free_buf:
        kfree(restricted_buf);
        return ERR_PTR(ret);
diff --git a/drivers/dma-buf/heaps/restricted_heap.h 
b/drivers/dma-buf/heaps/restricted_heap.h
index b448f77616ac..5783275d5714 100644
--- a/drivers/dma-buf/heaps/restricted_heap.h
+++ b/drivers/dma-buf/heaps/restricted_heap.h
@@ -15,6 +15,18 @@ struct restricted_buffer {
 
 struct restricted_heap {
        const char              *name;
+
+       const struct restricted_heap_ops *ops;
+};
+
+struct restricted_heap_ops {
+       int     (*heap_init)(struct restricted_heap *rheap);
+
+       int     (*alloc)(struct restricted_heap *rheap, struct 
restricted_buffer *buf);
+       void    (*free)(struct restricted_heap *rheap, struct restricted_buffer 
*buf);
+
+       int     (*restrict_buf)(struct restricted_heap *rheap, struct 
restricted_buffer *buf);
+       void    (*unrestrict_buf)(struct restricted_heap *rheap, struct 
restricted_buffer *buf);
 };
 
 int restricted_heap_add(struct restricted_heap *rheap);
-- 
2.25.1