Commit 7764222d authored by Thomas Hellström's avatar Thomas Hellström Committed by Rodrigo Vivi
Browse files

drm/xe: Disallow pinning dma-bufs in VRAM 



For now only support pinning in TT memory, for two reasons:
1) Avoid pinning in a placement not accessible to some importers.
2) Pinning in VRAM requires PIN accounting which is a to-do.

v2:
- Adjust the dma-buf kunit test accordingly.

Suggested-by: default avatarOded Gabbay <ogabbay@kernel.org>
Signed-off-by: default avatarThomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarOded Gabbay <ogabbay@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230920095001.5539-1-thomas.hellstrom@linux.intel.com


Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent d435a039

drivers/gpu/drm/xe/tests/xe_dma_buf.c

+12 −4
Original line number Diff line number Diff line
@@ -149,10 +149,18 @@ static void xe_test_dmabuf_import_same_driver(struct xe_device *xe) 
			/* Is everything where we expect it to be? */

			xe_bo_lock(import_bo, false);

			err = xe_bo_validate(import_bo, NULL, false);

			if (err && err != -EINTR && err != -ERESTARTSYS)

				KUNIT_FAIL(test,

					   "xe_bo_validate() failed with err=%d\n", err);



			/* Pinning in VRAM is not allowed. */

			if (!is_dynamic(params) &&

			    params->force_different_devices &&

			    !(params->mem_mask & XE_BO_CREATE_SYSTEM_BIT))

				KUNIT_EXPECT_EQ(test, err, -EINVAL);

			/* Otherwise only expect interrupts or success. */

			else if (err && err != -EINTR && err != -ERESTARTSYS)

				KUNIT_EXPECT_TRUE(test, !err || err == -EINTR ||

						  err == -ERESTARTSYS);



			if (!err)

				check_residency(test, bo, import_bo, dmabuf);

			xe_bo_unlock(import_bo);

		}

drivers/gpu/drm/xe/xe_dma_buf.c

+21 −4
Original line number Diff line number Diff line
@@ -49,13 +49,30 @@ static int xe_dma_buf_pin(struct dma_buf_attachment *attach) 
{

	struct drm_gem_object *obj = attach->dmabuf->priv;

	struct xe_bo *bo = gem_to_xe_bo(obj);

	struct xe_device *xe = xe_bo_device(bo);

	int ret;



	/*

	 * Migrate to TT first to increase the chance of non-p2p clients

	 * can attach.

	 * For now only support pinning in TT memory, for two reasons:

	 * 1) Avoid pinning in a placement not accessible to some importers.

	 * 2) Pinning in VRAM requires PIN accounting which is a to-do.

	 */

	(void)xe_bo_migrate(bo, XE_PL_TT);

	xe_bo_pin_external(bo);

	if (xe_bo_is_pinned(bo) && bo->ttm.resource->placement != XE_PL_TT) {

		drm_dbg(&xe->drm, "Can't migrate pinned bo for dma-buf pin.\n");

		return -EINVAL;

	}



	ret = xe_bo_migrate(bo, XE_PL_TT);

	if (ret) {

		if (ret != -EINTR && ret != -ERESTARTSYS)

			drm_dbg(&xe->drm,

				"Failed migrating dma-buf to TT memory: %pe\n",

				ERR_PTR(ret));

		return ret;

	}



	ret = xe_bo_pin_external(bo);

	xe_assert(xe, !ret);



	return 0;

}