drm/ttm/nouveau: don't call tt destroy callback on alloc failure.

This is confusing, and from my reading of all the drivers only
nouveau got this right.

Just make the API act under driver control of it's own allocation
failing, and don't call destroy, if the page table fails to
create there is nothing to cleanup here.

(I'm willing to believe I've missed something here, so please
review deeply).

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200728041736.20689-1-airlied@gmail.com

diff --git a/drivers/gpu/drm/nouveau/nouveau_sgdma.c b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
index 20b6d0b3de5ce0d42c27f07572c8d0ae6346427d..c3ccf661b7a67f7ecfb99a14dbe0bb49914eed40 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_sgdma.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
@@ -95,12 +95,9 @@ nouveau_sgdma_create_ttm(struct ttm_buffer_object *bo, uint32_t page_flags)
        else
                nvbe->ttm.ttm.func = &nv50_sgdma_backend;
 
-       if (ttm_dma_tt_init(&nvbe->ttm, bo, page_flags))
-               /*
-                * A failing ttm_dma_tt_init() will call ttm_tt_destroy()
-                * and thus our nouveau_sgdma_destroy() hook, so we don't need
-                * to free nvbe here.
-                */
+       if (ttm_dma_tt_init(&nvbe->ttm, bo, page_flags)) {
+               kfree(nvbe);
                return NULL;
+       }
        return &nvbe->ttm.ttm;
 }

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index bab67873cfd4c14f26e752c1afbb231b79337bc1..9d1c7177384cf43041736bfc7fc8987ced603189 100644 (file)
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -244,7 +244,6 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
        ttm_tt_init_fields(ttm, bo, page_flags);
 
        if (ttm_tt_alloc_page_directory(ttm)) {
-               ttm_tt_destroy(ttm);
                pr_err("Failed allocating page table\n");
                return -ENOMEM;
        }
@@ -268,7 +267,6 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
 
        INIT_LIST_HEAD(&ttm_dma->pages_list);
        if (ttm_dma_tt_alloc_page_directory(ttm_dma)) {
-               ttm_tt_destroy(ttm);
                pr_err("Failed allocating page table\n");
                return -ENOMEM;
        }
@@ -290,7 +288,6 @@ int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
        else
                ret = ttm_dma_tt_alloc_page_directory(ttm_dma);
        if (ret) {
-               ttm_tt_destroy(ttm);
                pr_err("Failed allocating page table\n");
                return -ENOMEM;
        }