Re: [RFC PATCH V7 1/9] drm/xe: Link VRAM object with gpu buddy

[Matthew Brost <matthew.brost@intel.com>]

On Mon, Apr 13, 2026 at 06:46:22PM +0530, Tejas Upadhyay wrote:
> Setup to link TTM buffer object inside gpu buddy. This functionality
> is critical for supporting the memory page offline feature on CRI,
> where identified faulty pages must be traced back to their
> originating buffer for safe removal.
> 
> V2(MattB): Clear block->private in xe_ttm_vram_mgr_del as well
> 
> Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>

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

> ---
>  drivers/gpu/drm/xe/xe_ttm_vram_mgr.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
> index 5fd0d5506a7e..01a9b92772f8 100644
> --- a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
> +++ b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
> @@ -54,6 +54,7 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
>  	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
>  	struct xe_ttm_vram_mgr_resource *vres;
>  	struct gpu_buddy *mm = &mgr->mm;
> +	struct gpu_buddy_block *block;
>  	u64 size, min_page_size;
>  	unsigned long lpfn;
>  	int err;
> @@ -138,6 +139,8 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
>  	}
>  
>  	mgr->visible_avail -= vres->used_visible_size;
> +	list_for_each_entry(block, &vres->blocks, link)
> +		block->private = tbo;
>  	mutex_unlock(&mgr->lock);
>  
>  	if (!(vres->base.placement & TTM_PL_FLAG_CONTIGUOUS) &&
> @@ -176,8 +179,11 @@ static void xe_ttm_vram_mgr_del(struct ttm_resource_manager *man,
>  		to_xe_ttm_vram_mgr_resource(res);
>  	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
>  	struct gpu_buddy *mm = &mgr->mm;
> +	struct gpu_buddy_block *block;
>  
>  	mutex_lock(&mgr->lock);
> +	list_for_each_entry(block, &vres->blocks, link)
> +		block->private = NULL;
>  	gpu_buddy_free_list(mm, &vres->blocks, 0);
>  	mgr->visible_avail += vres->used_visible_size;
>  	mutex_unlock(&mgr->lock);
> -- 
> 2.52.0
>