Commit eb289a5f authored by Thomas Hellström's avatar Thomas Hellström
Browse files

drm/xe: Convert xe_dma_buf.c for exhaustive eviction 



Convert dma-buf migration to XE_PL_TT and dma-buf import to
support exhaustive eviction, using xe_validation_guard().
It seems unlikely that the import would result in an -ENOMEM,
but convert import anyway for completeness.

The dma-buf map_attachment() functionality unfortunately doesn't
support passing a drm_exec, which means that foreign devices
validating a dma-buf that we exported will not, unless they are
xeKMD devices, participate in the exhaustive eviction scheme.

v2:
- Avoid gotos from within xe_validation_guard(). (Matt Brost)
- Adapt to signature change of xe_validation_guard(). (Matt Brost)
- Remove an unneeded (void)ret. (Matt Brost)
- Fix up an error path.

Signed-off-by: default avatarThomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20250908101246.65025-9-thomas.hellstrom@linux.intel.com
parent 7bcb6e38

drivers/gpu/drm/xe/xe_dma_buf.c

+41 −20
Original line number Diff line number Diff line
@@ -163,16 +163,26 @@ static int xe_dma_buf_begin_cpu_access(struct dma_buf *dma_buf, 
	struct xe_bo *bo = gem_to_xe_bo(obj);

	bool reads =  (direction == DMA_BIDIRECTIONAL ||

		       direction == DMA_FROM_DEVICE);

	struct drm_exec *exec = XE_VALIDATION_UNIMPLEMENTED;

	struct xe_validation_ctx ctx;

	struct drm_exec exec;

	int ret = 0;



	if (!reads)

		return 0;



	/* Can we do interruptible lock here? */

	xe_bo_lock(bo, false);

	(void)xe_bo_migrate(bo, XE_PL_TT, NULL, exec);

	xe_bo_unlock(bo);

	xe_validation_guard(&ctx, &xe_bo_device(bo)->val, &exec, (struct xe_val_flags) {}, ret) {

		ret = drm_exec_lock_obj(&exec, &bo->ttm.base);

		drm_exec_retry_on_contention(&exec);

		if (ret)

			break;



		ret = xe_bo_migrate(bo, XE_PL_TT, NULL, &exec);

		drm_exec_retry_on_contention(&exec);

		xe_validation_retry_on_oom(&ctx, &ret);

	}



	/* If we failed, cpu-access takes place in current placement. */

	return 0;

}
@@ -211,25 +221,36 @@ xe_dma_buf_init_obj(struct drm_device *dev, struct xe_bo *storage, 
{

	struct dma_resv *resv = dma_buf->resv;

	struct xe_device *xe = to_xe_device(dev);

	struct drm_exec *exec = XE_VALIDATION_UNIMPLEMENTED;

	struct xe_validation_ctx ctx;

	struct drm_gem_object *dummy_obj;

	struct drm_exec exec;

	struct xe_bo *bo;

	int ret;

	int ret = 0;



	dummy_obj = drm_gpuvm_resv_object_alloc(&xe->drm);

	if (!dummy_obj)

		return ERR_PTR(-ENOMEM);



	dummy_obj->resv = resv;

	xe_validation_guard(&ctx, &xe->val, &exec, (struct xe_val_flags) {}, ret) {

		ret = drm_exec_lock_obj(&exec, dummy_obj);

		drm_exec_retry_on_contention(&exec);

		if (ret)

			break;



	dma_resv_lock(resv, NULL);

		bo = ___xe_bo_create_locked(xe, storage, NULL, resv, NULL, dma_buf->size,

					    0, /* Will require 1way or 2way for vm_bind */

				    ttm_bo_type_sg, XE_BO_FLAG_SYSTEM, exec);

					    ttm_bo_type_sg, XE_BO_FLAG_SYSTEM, &exec);

		drm_exec_retry_on_contention(&exec);

		if (IS_ERR(bo)) {

			ret = PTR_ERR(bo);

		goto error;

			xe_validation_retry_on_oom(&ctx, &ret);

			break;

		}

	dma_resv_unlock(resv);



	return &bo->ttm.base;

	}

	drm_gem_object_put(dummy_obj);



error:

	dma_resv_unlock(resv);

	return ERR_PTR(ret);

	return ret ? ERR_PTR(ret) : &bo->ttm.base;

}



static void xe_dma_buf_move_notify(struct dma_buf_attachment *attach)