[PATCH 1/4] drm/xe/vm: Use onion unwind for xe_vma_userptr_pin_pages()

[Matthew Brost]

On Fri, Aug 18, 2023 at 05:08:42PM +0200, Thomas Hellström wrote:
> Use onion error unwind since that makes the function easier to read
> and extend. No functional change.
> 
> Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>

Reviewed-by: Matthew Brost <matthew.brost at intel.com>

> ---
>  drivers/gpu/drm/xe/xe_vm.c | 37 +++++++++++++++++++------------------
>  1 file changed, 19 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> index 2e99f865d7ec..8bf7f62e6548 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -116,19 +116,17 @@ int xe_vma_userptr_pin_pages(struct xe_vma *vma)
>  		kthread_unuse_mm(vma->userptr.notifier.mm);
>  		mmput(vma->userptr.notifier.mm);
>  	}
> -mm_closed:
>  	if (ret)
> -		goto out;
> +		goto out_release_pages;
>  
>  	ret = sg_alloc_table_from_pages_segment(&vma->userptr.sgt, pages,
>  						pinned, 0,
>  						(u64)pinned << PAGE_SHIFT,
>  						xe_sg_segment_size(xe->drm.dev),
>  						GFP_KERNEL);
> -	if (ret) {
> -		vma->userptr.sg = NULL;
> -		goto out;
> -	}
> +	if (ret)
> +		goto out_release_pages;
> +
>  	vma->userptr.sg = &vma->userptr.sgt;
>  
>  	ret = dma_map_sgtable(xe->drm.dev, vma->userptr.sg,
> @@ -136,11 +134,8 @@ int xe_vma_userptr_pin_pages(struct xe_vma *vma)
>  			      DMA_BIDIRECTIONAL,
>  			      DMA_ATTR_SKIP_CPU_SYNC |
>  			      DMA_ATTR_NO_KERNEL_MAPPING);
> -	if (ret) {
> -		sg_free_table(vma->userptr.sg);
> -		vma->userptr.sg = NULL;
> -		goto out;
> -	}
> +	if (ret)
> +		goto out_free_sg;
>  
>  	for (i = 0; i < pinned; ++i) {
>  		if (!read_only) {
> @@ -152,17 +147,23 @@ int xe_vma_userptr_pin_pages(struct xe_vma *vma)
>  		mark_page_accessed(pages[i]);
>  	}
>  
> -out:
>  	release_pages(pages, pinned);
>  	kvfree(pages);
>  
> -	if (!(ret < 0)) {
> -		vma->userptr.notifier_seq = notifier_seq;
> -		if (xe_vma_userptr_check_repin(vma) == -EAGAIN)
> -			goto retry;
> -	}
> +	vma->userptr.notifier_seq = notifier_seq;
> +	if (xe_vma_userptr_check_repin(vma) == -EAGAIN)
> +		goto retry;
> +
> +	return 0;
>  
> -	return ret < 0 ? ret : 0;
> +out_free_sg:
> +	sg_free_table(vma->userptr.sg);
> +	vma->userptr.sg = NULL;
> +out_release_pages:
> +	release_pages(pages, pinned);
> +mm_closed:
> +	kvfree(pages);
> +	return ret;
>  }
>  
>  static bool preempt_fences_waiting(struct xe_vm *vm)
> -- 
> 2.41.0
>