Allows us to gut a BO of it's backing store when the driver says that it
isn't needed any more.
Signed-off-by: Christian König <christian.koenig at amd.com>
---
drivers/gpu/drm/ttm/ttm_bo.c | 15 ++++++++++++---
drivers/gpu/drm/ttm/ttm_bo_util.c | 24 ++++++++++++++++++++++++
include/drm/ttm/ttm_bo_driver.h | 9 +++++++++
3 files changed, 45 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index ad142a92eb80..98e06f8bf23b 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -622,14 +622,23 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo,
reservation_object_assert_held(bo->resv);
+ placement.num_placement = 0;
+ placement.num_busy_placement = 0;
+ bdev->driver->evict_flags(bo, &placement);
+
+ if (!placement.num_placement && !placement.num_busy_placement) {
+ ret = ttm_bo_pipeline_gutting(bo);
+ if (ret)
+ return ret;
+
+ return ttm_tt_create(bo, false);
+ }
+
evict_mem = bo->mem;
evict_mem.mm_node = NULL;
evict_mem.bus.io_reserved_vm = false;
evict_mem.bus.io_reserved_count = 0;
- placement.num_placement = 0;
- placement.num_busy_placement = 0;
- bdev->driver->evict_flags(bo, &placement);
ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
if (ret) {
if (ret != -ERESTARTSYS) {
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 6d6a3f46143b..1f730b3f18e5 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -801,3 +801,27 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo,
return 0;
}
EXPORT_SYMBOL(ttm_bo_pipeline_move);
+
+int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo)
+{
+ struct ttm_buffer_object *ghost;
+ int ret;
+
+ ret = ttm_buffer_object_transfer(bo, &ghost);
+ if (ret)
+ return ret;
+
+ ret = reservation_object_copy_fences(ghost->resv, bo->resv);
+ /* Last resort, wait for the BO to be idle when we are OOM */
+ if (ret)
+ ttm_bo_wait(bo, false, false);
+
+ memset(&bo->mem, 0, sizeof(bo->mem));
+ bo->mem.mem_type = TTM_PL_SYSTEM;
+ bo->ttm = NULL;
+
+ ttm_bo_unreserve(ghost);
+ ttm_bo_unref(&ghost);
+
+ return 0;
+}
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index f8e2515b401f..39cd6b086d3a 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -849,6 +849,15 @@ int ttm_bo_pipeline_move(struct ttm_buffer_object *bo,
struct dma_fence *fence, bool evict,
struct ttm_mem_reg *new_mem);
+/**
+ * ttm_bo_pipeline_gutting.
+ *
+ * @bo: A pointer to a struct ttm_buffer_object.
+ *
+ * Pipelined gutting a BO of it's backing store.
+ */
+int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo);
+
/**
* ttm_io_prot
*
--
2.14.1
