# Re: \[PATCH v9 02/14\] swiotlb: Refactor swiotlb\_create\_debugfs

- From: Christoph Hellwig \<hch@lst.de\>
- Date: 2021-06-14 06:17:44 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2021/06/1412585
- Thread: https://ratatoskr.run/linux-devicetree/2021/06/1411409/t.md

```text
On Fri, Jun 11, 2021 at 11:26:47PM +0800, Claire Chang wrote:
> Split the debugfs creation to make the code reusable for supporting
> different bounce buffer pools, e.g. restricted DMA pool.
> 
> Signed-off-by: Claire Chang <redacted>
> ---
>  kernel/dma/swiotlb.c | 23 ++++++++++++++++-------
>  1 file changed, 16 insertions(+), 7 deletions(-)
> 
> diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
> index 1a1208c81e85..8a3e2b3b246d 100644
> --- a/kernel/dma/swiotlb.c
> +++ b/kernel/dma/swiotlb.c
> @@ -64,6 +64,9 @@
>  enum swiotlb_force swiotlb_force;
>  
>  struct io_tlb_mem *io_tlb_default_mem;
> +#ifdef CONFIG_DEBUG_FS
> +static struct dentry *debugfs_dir;
> +#endif

What about moving this declaration into the main CONFIG_DEBUG_FS block
near the functions using it?

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
```