[Intel-gfx] [PATCH v2] drm/i915: Unwind conversion to i915_gem_phys_ops on failure

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> The physical object is treated as permanently pinned. If we fail to take
> this initial pin during i915_gem_object_attach_phys() we need to revert
> it back to an ordinary shmemfs object before reporting the failure.
>
> v2: git-add
>
> Reported-by: Mika Kuoppala <mika.kuoppala at intel.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala at intel.com>

Reviewed-by: Mika Kuoppala <mika.kuoppala at intel.com>

> ---
>  drivers/gpu/drm/i915/i915_gem.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 71297920fdf4..dc799db0446c 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -313,6 +313,8 @@ static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
>  	.release = i915_gem_object_release_phys,
>  };
>  
> +static const struct drm_i915_gem_object_ops i915_gem_object_ops;
> +
>  int i915_gem_object_unbind(struct drm_i915_gem_object *obj)
>  {
>  	struct i915_vma *vma;
> @@ -586,9 +588,18 @@ i915_gem_object_attach_phys(struct drm_i915_gem_object *obj,
>  	if (obj->mm.pages)
>  		return -EBUSY;
>  
> +	GEM_BUG_ON(obj->ops != &i915_gem_object_ops);
>  	obj->ops = &i915_gem_phys_ops;
>  
> -	return i915_gem_object_pin_pages(obj);
> +	ret = i915_gem_object_pin_pages(obj);
> +	if (ret)
> +		goto err_xfer;
> +
> +	return 0;
> +
> +err_xfer:
> +	obj->ops = &i915_gem_object_ops;
> +	return ret;
>  }
>  
>  static int
> -- 
> 2.11.0