Commit 58dc430d authored by Himal Prasad Ghimiray's avatar Himal Prasad Ghimiray
Browse files

drm/xe/vm: Add helper to check for default VMA memory attributes 



Introduce a new helper function `xe_vma_has_default_mem_attrs()` to
determine whether a VMA's memory attributes are set to their default
values. This includes checks for atomic access, PAT index, and preferred
location.

Also, add a new field `default_pat_index` to `struct xe_vma_mem_attr`
to track the initial PAT index set during the first bind. This helps
distinguish between default and user-modified pat index, such as those
changed via madvise.

Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20250821173104.3030148-18-himal.prasad.ghimiray@intel.com


Signed-off-by: default avatarHimal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
parent 002f817d

drivers/gpu/drm/xe/xe_vm.c

+24 −0
Original line number Diff line number Diff line
@@ -2640,6 +2640,29 @@ static int xe_vma_op_commit(struct xe_vm *vm, struct xe_vma_op *op) 
	return err;

}



/**

 * xe_vma_has_default_mem_attrs - Check if a VMA has default memory attributes

 * @vma: Pointer to the xe_vma structure to check

 *

 * This function determines whether the given VMA (Virtual Memory Area)

 * has its memory attributes set to their default values. Specifically,

 * it checks the following conditions:

 *

 * - `atomic_access` is `DRM_XE_VMA_ATOMIC_UNDEFINED`

 * - `pat_index` is equal to `default_pat_index`

 * - `preferred_loc.devmem_fd` is `DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE`

 * - `preferred_loc.migration_policy` is `DRM_XE_MIGRATE_ALL_PAGES`

 *

 * Return: true if all attributes are at their default values, false otherwise.

 */

bool xe_vma_has_default_mem_attrs(struct xe_vma *vma)

{

	return (vma->attr.atomic_access == DRM_XE_ATOMIC_UNDEFINED &&

		vma->attr.pat_index ==  vma->attr.default_pat_index &&

		vma->attr.preferred_loc.devmem_fd == DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE &&

		vma->attr.preferred_loc.migration_policy == DRM_XE_MIGRATE_ALL_PAGES);

}



static int vm_bind_ioctl_ops_parse(struct xe_vm *vm, struct drm_gpuva_ops *ops,

				   struct xe_vma_ops *vops)

{
@@ -2672,6 +2695,7 @@ static int vm_bind_ioctl_ops_parse(struct xe_vm *vm, struct drm_gpuva_ops *ops, 
					.migration_policy = DRM_XE_MIGRATE_ALL_PAGES,

				},

				.atomic_access = DRM_XE_ATOMIC_UNDEFINED,

				.default_pat_index = op->map.pat_index,

				.pat_index = op->map.pat_index,

			};

drivers/gpu/drm/xe/xe_vm.h

+2 −0
Original line number Diff line number Diff line
@@ -66,6 +66,8 @@ static inline bool xe_vm_is_closed_or_banned(struct xe_vm *vm) 
struct xe_vma *

xe_vm_find_overlapping_vma(struct xe_vm *vm, u64 start, u64 range);



bool xe_vma_has_default_mem_attrs(struct xe_vma *vma);



/**

 * xe_vm_has_scratch() - Whether the vm is configured for scratch PTEs

 * @vm: The vm

drivers/gpu/drm/xe/xe_vm_types.h

+6 −0
Original line number Diff line number Diff line
@@ -103,8 +103,14 @@ struct xe_vma_mem_attr { 
	 */

	u32 atomic_access;



	/**

	 * @default_pat_index: The pat index for VMA set during first bind by user.

	 */

	u16 default_pat_index;



	/**

	 * @pat_index: The pat index to use when encoding the PTEs for this vma.

	 * same as default_pat_index unless overwritten by madvise.

	 */

	u16 pat_index;

};