[PATCH] drm/ttm: callback move_notify any time bo placement change v3

[j.glisse at gmail.com]

From: Jerome Glisse <jglisse at redhat.com>

Previously we were calling back move_notify in error path when the
bo is returned to it's original position or when destroy the bo.
When destroying the bo set the new mem placement as NULL when calling
back in the driver.

Updating nouveau to deal with NULL placement properly.

v2: reserve the object before calling move_notify in bo destroy path
    at that point ttm should be the only piece of code interacting
    with the object so atomic_set is safe here.
v3: callback move notify only once the bo is in its new position
    call move notify want swaping out the buffer

Reviewed-by: Jerome Glisse <jglisse at redhat.com>
---
 drivers/gpu/drm/nouveau/nouveau_bo.c |    4 ++--
 drivers/gpu/drm/ttm/ttm_bo.c         |   17 +++++++++++++----
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index 857bca4..f12dd0f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -815,10 +815,10 @@ nouveau_bo_move_ntfy(struct ttm_buffer_object *bo, struct ttm_mem_reg *new_mem)
 	struct nouveau_vma *vma;
 
 	list_for_each_entry(vma, &nvbo->vma_list, head) {
-		if (new_mem->mem_type == TTM_PL_VRAM) {
+		if (new_mem && new_mem->mem_type == TTM_PL_VRAM) {
 			nouveau_vm_map(vma, new_mem->mm_node);
 		} else
-		if (new_mem->mem_type == TTM_PL_TT &&
+		if (new_mem && new_mem->mem_type == TTM_PL_TT &&
 		    nvbo->page_shift == vma->vm->spg_shift) {
 			nouveau_vm_map_sg(vma, 0, new_mem->
 					  num_pages << PAGE_SHIFT,
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index de7ad99..0c1d821 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -147,6 +147,12 @@ static void ttm_bo_release_list(struct kref *list_kref)
 	BUG_ON(!list_empty(&bo->lru));
 	BUG_ON(!list_empty(&bo->ddestroy));
 
+	/* force bo to reserved, at this point we should be the only owner */
+	atomic_set(&bo->reserved, 1);
+	if (bdev->driver->move_notify)
+		bdev->driver->move_notify(bo, NULL);
+	atomic_set(&bo->reserved, 0);
+
 	if (bo->ttm)
 		ttm_tt_destroy(bo->ttm);
 	atomic_dec(&bo->glob->bo_count);
@@ -404,9 +410,6 @@ static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 		}
 	}
 
-	if (bdev->driver->move_notify)
-		bdev->driver->move_notify(bo, mem);
-
 	if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
 	    !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))
 		ret = ttm_bo_move_ttm(bo, evict, no_wait_reserve, no_wait_gpu, mem);
@@ -419,6 +422,9 @@ static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 	if (ret)
 		goto out_err;
 
+	if (bdev->driver->move_notify)
+		bdev->driver->move_notify(bo, mem);
+
 moved:
 	if (bo->evicted) {
 		ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);
@@ -1872,9 +1878,12 @@ static int ttm_bo_swapout(struct ttm_mem_shrink *shrink)
 	if (bo->bdev->driver->swap_notify)
 		bo->bdev->driver->swap_notify(bo);
 
+	if (bo->bdev->driver->move_notify)
+		bo->bdev->driver->move_notify(bo, NULL);
+
 	ret = ttm_tt_swapout(bo->ttm, bo->persistent_swap_storage);
-out:
 
+out:
 	/**
 	 *
 	 * Unreserve without putting on LRU to avoid swapping out an
-- 
1.7.7.1