Re: [RFC PATCH 2/7] drm/xe/svm: Use xe_vram_addr_to_region

[Matthew Auld <matthew.auld@intel.com>]

On 12/02/2026 16:34, Tejas Upadhyay wrote:
> Replace the direct use of block->private with the helper function
> xe_vram_addr_to_region to get vram region.
> 
> Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
> ---
>   drivers/gpu/drm/xe/xe_svm.c | 9 ++-------
>   1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
> index 213f0334518a..e773456af040 100644
> --- a/drivers/gpu/drm/xe/xe_svm.c
> +++ b/drivers/gpu/drm/xe/xe_svm.c
> @@ -762,7 +762,8 @@ static int xe_svm_populate_devmem_pfn(struct drm_pagemap_devmem *devmem_allocati
>   	int j = 0;
>   
>   	list_for_each_entry(block, blocks, link) {
> -		struct xe_vram_region *vr = block->private;
> +		u64 block_start = drm_buddy_block_offset(block);
> +		struct xe_vram_region *vr = xe_vram_addr_to_region(bo->tile->xe, block_start);

Oh, I think block_offset is the relative offset, which always starts 
from zero, but here you want the real addr, but that info comes from the 
region...

I was gonna say since you seem to already have bo->tile above, why not 
just pick the VRAM from that tile? Like with bo->tile->mem.vram? But I 
think bo->tile is NULL even here so above looks like it will crash?

What about looking at the bo flags or current ttm placement to figure 
out which VRAM this belongs to? There looks to already be 
res_to_mem_region() and you have res above.

>   		struct drm_buddy *buddy = vram_to_buddy(vr);
>   		u64 block_pfn = block_offset_to_pfn(devmem_allocation->dpagemap,
>   						    drm_buddy_block_offset(block));
> @@ -1033,9 +1034,7 @@ static int xe_drm_pagemap_populate_mm(struct drm_pagemap *dpagemap,
>   	struct dma_fence *pre_migrate_fence = NULL;
>   	struct xe_device *xe = vr->xe;
>   	struct device *dev = xe->drm.dev;
> -	struct drm_buddy_block *block;
>   	struct xe_validation_ctx vctx;
> -	struct list_head *blocks;
>   	struct drm_exec exec;
>   	struct xe_bo *bo;
>   	int err = 0, idx;
> @@ -1072,10 +1071,6 @@ static int xe_drm_pagemap_populate_mm(struct drm_pagemap *dpagemap,
>   					&dpagemap_devmem_ops, dpagemap, end - start,
>   					pre_migrate_fence);
>   
> -		blocks = &to_xe_ttm_vram_mgr_resource(bo->ttm.resource)->blocks;
> -		list_for_each_entry(block, blocks, link)
> -			block->private = vr;
> -
>   		xe_bo_get(bo);
>   
>   		/* Ensure the device has a pm ref while there are device pages active. */