drm/virtio: switch from ttm to gem shmem helpers

virtio-gpu basically needs a sg_table for the bo, to tell the host where
the backing pages for the object are.  So the gem shmem helpers are a
perfect fit.  Some drm_gem_object_funcs need thin wrappers to update the
host state, but otherwise the helpers handle everything just fine.

Once the fencing was sorted the switch was surprisingly easy and for the
most part just removing the ttm code.

v4: fix drm_gem_object_funcs name.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190829103301.3539-15-kraxel@redhat.com

1 files changed, 42 insertions, 106 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
index 6af2862c9a73..69a3d310ff70 100644
--- a/drivers/gpu/drm/virtio/virtgpu_object.c
+++ b/drivers/gpu/drm/virtio/virtgpu_object.c
@@ -25,8 +25,6 @@
 
 #include <linux/moduleparam.h>
 
-#include <drm/ttm/ttm_execbuf_util.h>
-
 #include "virtgpu_drv.h"
 
 static int virtio_gpu_virglrenderer_workaround = 1;
@@ -63,39 +61,45 @@ static void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t
 	}
 }
 
-static void virtio_gpu_ttm_bo_destroy(struct ttm_buffer_object *tbo)
+static void virtio_gpu_free_object(struct drm_gem_object *obj)
 {
-	struct virtio_gpu_object *bo;
-	struct virtio_gpu_device *vgdev;
-
-	bo = container_of(tbo, struct virtio_gpu_object, tbo);
-	vgdev = (struct virtio_gpu_device *)bo->gem_base.dev->dev_private;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+	struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
 
+	if (bo->pages)
+		virtio_gpu_object_detach(vgdev, bo);
 	if (bo->created)
 		virtio_gpu_cmd_unref_resource(vgdev, bo->hw_res_handle);
-	if (bo->pages)
-		virtio_gpu_object_free_sg_table(bo);
-	if (bo->vmap)
-		virtio_gpu_object_kunmap(bo);
-	drm_gem_object_release(&bo->gem_base);
 	virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
-	kfree(bo);
+
+	drm_gem_shmem_free_object(obj);
 }
 
-static void virtio_gpu_init_ttm_placement(struct virtio_gpu_object *vgbo)
+static const struct drm_gem_object_funcs virtio_gpu_gem_funcs = {
+	.free = virtio_gpu_free_object,
+	.open = virtio_gpu_gem_object_open,
+	.close = virtio_gpu_gem_object_close,
+
+	.print_info = drm_gem_shmem_print_info,
+	.pin = drm_gem_shmem_pin,
+	.unpin = drm_gem_shmem_unpin,
+	.get_sg_table = drm_gem_shmem_get_sg_table,
+	.vmap = drm_gem_shmem_vmap,
+	.vunmap = drm_gem_shmem_vunmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
+};
+
+struct drm_gem_object *virtio_gpu_create_object(struct drm_device *dev,
+						size_t size)
 {
-	u32 c = 1;
-
-	vgbo->placement.placement = &vgbo->placement_code;
-	vgbo->placement.busy_placement = &vgbo->placement_code;
-	vgbo->placement_code.fpfn = 0;
-	vgbo->placement_code.lpfn = 0;
-	vgbo->placement_code.flags =
-		TTM_PL_MASK_CACHING | TTM_PL_FLAG_TT |
-		TTM_PL_FLAG_NO_EVICT;
-	vgbo->placement.num_placement = c;
-	vgbo->placement.num_busy_placement = c;
+	struct virtio_gpu_object *bo;
+
+	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
+	if (!bo)
+		return NULL;
 
+	bo->base.base.funcs = &virtio_gpu_gem_funcs;
+	return &bo->base.base;
 }
 
 int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
@@ -104,27 +108,22 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
 			     struct virtio_gpu_fence *fence)
 {
 	struct virtio_gpu_object_array *objs = NULL;
+	struct drm_gem_shmem_object *shmem_obj;
 	struct virtio_gpu_object *bo;
-	size_t acc_size;
 	int ret;
 
 	*bo_ptr = NULL;
 
-	acc_size = ttm_bo_dma_acc_size(&vgdev->mman.bdev, params->size,
-				       sizeof(struct virtio_gpu_object));
+	params->size = roundup(params->size, PAGE_SIZE);
+	shmem_obj = drm_gem_shmem_create(vgdev->ddev, params->size);
+	if (IS_ERR(shmem_obj))
+		return PTR_ERR(shmem_obj);
+	bo = gem_to_virtio_gpu_obj(&shmem_obj->base);
 
-	bo = kzalloc(sizeof(struct virtio_gpu_object), GFP_KERNEL);
-	if (bo == NULL)
-		return -ENOMEM;
 	ret = virtio_gpu_resource_id_get(vgdev, &bo->hw_res_handle);
 	if (ret < 0)
 		goto err_free_gem;
 
-	params->size = roundup(params->size, PAGE_SIZE);
-	ret = drm_gem_object_init(vgdev->ddev, &bo->gem_base, params->size);
-	if (ret != 0)
-		goto err_put_id;
-
 	bo->dumb = params->dumb;
 
 	if (fence) {
@@ -132,7 +131,7 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
 		objs = virtio_gpu_array_alloc(1);
 		if (!objs)
 			goto err_put_id;
-		virtio_gpu_array_add_obj(objs, &bo->gem_base);
+		virtio_gpu_array_add_obj(objs, &bo->base.base);
 
 		ret = virtio_gpu_array_lock_resv(objs);
 		if (ret != 0)
@@ -147,15 +146,11 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
 					       objs, fence);
 	}
 
-	virtio_gpu_init_ttm_placement(bo);
-	ret = ttm_bo_init(&vgdev->mman.bdev, &bo->tbo, params->size,
-			  ttm_bo_type_device, &bo->placement, 0,
-			  true, acc_size, NULL,
-			  bo->gem_base.resv,
-			  &virtio_gpu_ttm_bo_destroy);
-	/* ttm_bo_init failure will call the destroy */
-	if (ret != 0)
+	ret = virtio_gpu_object_attach(vgdev, bo, NULL);
+	if (ret != 0) {
+		virtio_gpu_free_object(&shmem_obj->base);
 		return ret;
+	}
 
 	*bo_ptr = bo;
 	return 0;
@@ -165,65 +160,6 @@ err_put_objs:
 err_put_id:
 	virtio_gpu_resource_id_put(vgdev, bo->hw_res_handle);
 err_free_gem:
-	kfree(bo);
+	drm_gem_shmem_free_object(&shmem_obj->base);
 	return ret;
 }
-
-void virtio_gpu_object_kunmap(struct virtio_gpu_object *bo)
-{
-	bo->vmap = NULL;
-	ttm_bo_kunmap(&bo->kmap);
-}
-
-int virtio_gpu_object_kmap(struct virtio_gpu_object *bo)
-{
-	bool is_iomem;
-	int r;
-
-	WARN_ON(bo->vmap);
-
-	r = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages, &bo->kmap);
-	if (r)
-		return r;
-	bo->vmap = ttm_kmap_obj_virtual(&bo->kmap, &is_iomem);
-	return 0;
-}
-
-int virtio_gpu_object_get_sg_table(struct virtio_gpu_device *qdev,
-				   struct virtio_gpu_object *bo)
-{
-	int ret;
-	struct page **pages = bo->tbo.ttm->pages;
-	int nr_pages = bo->tbo.num_pages;
-	struct ttm_operation_ctx ctx = {
-		.interruptible = false,
-		.no_wait_gpu = false
-	};
-
-	/* wtf swapping */
-	if (bo->pages)
-		return 0;
-
-	if (bo->tbo.ttm->state == tt_unpopulated)
-		bo->tbo.ttm->bdev->driver->ttm_tt_populate(bo->tbo.ttm, &ctx);
-	bo->pages = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
-	if (!bo->pages)
-		goto out;
-
-	ret = sg_alloc_table_from_pages(bo->pages, pages, nr_pages, 0,
-					nr_pages << PAGE_SHIFT, GFP_KERNEL);
-	if (ret)
-		goto out;
-	return 0;
-out:
-	kfree(bo->pages);
-	bo->pages = NULL;
-	return -ENOMEM;
-}
-
-void virtio_gpu_object_free_sg_table(struct virtio_gpu_object *bo)
-{
-	sg_free_table(bo->pages);
-	kfree(bo->pages);
-	bo->pages = NULL;
-}