[RFC PATCH v7 12/13] dma-buf: system_heap: Allocate shared buffers using CoCo shared memory allocator

Catalin Marinas catalin.marinas at arm.com
Tue Sep 22 09:39:04 PDT 2026


On Mon, Sep 21, 2026 at 08:18:46PM +0530, Aneesh Kumar K.V (Arm) wrote:
> @@ -405,6 +396,7 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap,
>  {
>  	struct system_heap_buffer *buffer;
>  	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
> +	struct cc_shared_layout layout;
>  	unsigned long size_remaining = len;
>  	unsigned long sg_remaining = len;
>  	unsigned int max_order = orders[0];
> @@ -417,6 +409,14 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap,
>  	struct page *page, *tmp_page;
>  	int i, ret = -ENOMEM;
>  
> +	if (cc_shared) {
> +		ret = cc_shared_calc_layout(len, &layout);

You should not override 'ret' here, it was set to -ENOMEM for a reason.
cc_shared_calc_layout() succeeds resetting 'ret' and some further down
allocation failure, goto free will return ERR_PTR(0).

-- 
Catalin



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