On Mon, Jan 25, 2021 at 11:32:57PM -0800, John Stultz wrote:

On Thu, Jan 21, 2021 at 9:55 AM Minchan Kim [off-list ref] wrote:

Hey Minchan,
  Thanks for sending this out! I'm still working through testing with
this patch set, so I may have some more feedback tomorrow, but a few
quick items I did hit below.

quoted

+
+#define CHUNK_PREFIX "chunk-"
+
+static int register_chunk_heap(struct chunk_heap *chunk_heap_info)
+{
+       struct dma_heap_export_info exp_info;
+       const char *name = cma_get_name(chunk_heap_info->cma);
+       size_t len = strlen(CHUNK_PREFIX) + strlen(name) + 1;
+       char *buf = kmalloc(len, GFP_KERNEL);
+
+       if (!buf)
+               return -ENOMEM;
+
+       sprintf(buf, CHUNK_PREFIX"%s", cma_get_name(chunk_heap_info->cma));
+       buf[len] = '\0';
+
+       exp_info.name = buf;
+       exp_info.name = cma_get_name(chunk_heap_info->cma);

I think you intended to delete this line, as it's overwriting your
prefixed name.

Hi John,

You're right. Will fix it.

quoted

+       exp_info.ops = &chunk_heap_ops;
+       exp_info.priv = chunk_heap_info;
+
+       chunk_heap_info->heap = dma_heap_add(&exp_info);
+       if (IS_ERR(chunk_heap_info->heap)) {
+               kfree(buf);
+               return PTR_ERR(chunk_heap_info->heap);
+       }
+
+       return 0;
+}
+
+static int __init chunk_heap_init(void)
+{
+       unsigned int i;
+
+       for (i = 0; i < chunk_heap_count; i++)
+               register_chunk_heap(&chunk_heaps[i]);
+
+       return 0;
+}
+module_init(chunk_heap_init);
+
+#ifdef CONFIG_OF_EARLY_FLATTREE
+
+static int __init dmabuf_chunk_heap_area_init(struct reserved_mem *rmem)
+{
+       int ret;
+       struct cma *cma;
+       struct chunk_heap *chunk_heap_info;
+       const __be32 *chunk_order;
+
+       phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+       phys_addr_t mask = align - 1;
+
+       if ((rmem->base & mask) || (rmem->size & mask)) {
+               pr_err("Incorrect alignment for CMA region\n");
+               return -EINVAL;

Passing this check can be tough if you're using dynamically assigned
rmem, so it might be helpful for debugging to print the base/size/mask
values?

Let me fold this into next respin.

diff --git a/drivers/dma-buf/heaps/chunk_heap.c b/drivers/dma-buf/heaps/chunk_heap.c
index 6fe8e69d108f..cc2ed5341b54 100644
--- a/drivers/dma-buf/heaps/chunk_heap.c
+++ b/drivers/dma-buf/heaps/chunk_heap.c

@@ -456,7 +456,8 @@ static int __init dmabuf_chunk_heap_area_init(struct reserved_mem *rmem)
        phys_addr_t mask = align - 1;

        if ((rmem->base & mask) || (rmem->size & mask)) {
-               pr_err("Incorrect alignment for CMA region\n");
+               pr_err("Incorrect alignment for CMA region: base %pa size %pa mask %pa\n",
+                               rmem->base, rmem->size, mask);
                return -EINVAL;
        }

Thanks for the review, John!