Linux Virtualization - Jun 2019 - [PATCH v5 07/12] drm/virtio: add virtio_gpu_object_array & helpers

Some helper functions to manage an array of gem objects.

v5: some small optimizations (Chia-I Wu).
v4: make them virtio-private instead of generic helpers.

Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_drv.h | 10 +++++++
 drivers/gpu/drm/virtio/virtgpu_gem.c | 45 ++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h
b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 07f6001ea91e..98d646789d23 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -84,6 +84,11 @@ struct virtio_gpu_object {
 #define gem_to_virtio_gpu_obj(gobj) \
 	container_of((gobj), struct virtio_gpu_object, gem_base)
 
+struct virtio_gpu_object_array {
+	u32 nents;
+	struct drm_gem_object *objs[];
+};
+
 struct virtio_gpu_vbuffer;
 struct virtio_gpu_device;
 
@@ -251,6 +256,11 @@ int virtio_gpu_mode_dumb_mmap(struct drm_file *file_priv,
 			      struct drm_device *dev,
 			      uint32_t handle, uint64_t *offset_p);
 
+struct virtio_gpu_object_array *virtio_gpu_array_alloc(u32 nents);
+struct virtio_gpu_object_array*
+virtio_gpu_array_from_handles(struct drm_file *drm_file, u32 *handles, u32
nents);
+void virtio_gpu_array_put_free(struct virtio_gpu_object_array *objs);
+
 /* virtio vg */
 int virtio_gpu_alloc_vbufs(struct virtio_gpu_device *vgdev);
 void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev);
diff --git a/drivers/gpu/drm/virtio/virtgpu_gem.c
b/drivers/gpu/drm/virtio/virtgpu_gem.c
index 9c9ad3b14080..74ba3f0db4f1 100644
--- a/drivers/gpu/drm/virtio/virtgpu_gem.c
+++ b/drivers/gpu/drm/virtio/virtgpu_gem.c
@@ -169,3 +169,48 @@ void virtio_gpu_gem_object_close(struct drm_gem_object
*obj,
 						qobj->hw_res_handle);
 	virtio_gpu_object_unreserve(qobj);
 }
+
+struct virtio_gpu_object_array *virtio_gpu_array_alloc(u32 nents)
+{
+	struct virtio_gpu_object_array *objs;
+	size_t size = sizeof(*objs) + sizeof(objs->objs[0]) * nents;
+
+	objs = kmalloc(size, GFP_KERNEL);
+	return objs;
+}
+
+static void virtio_gpu_array_free(struct virtio_gpu_object_array *objs)
+{
+	kfree(objs);
+}
+
+struct virtio_gpu_object_array*
+virtio_gpu_array_from_handles(struct drm_file *drm_file, u32 *handles, u32
nents)
+{
+	struct virtio_gpu_object_array *objs;
+	u32 i;
+
+	objs = virtio_gpu_array_alloc(nents);
+	if (!objs)
+		return NULL;
+
+	for (i = 0; i < nents; i++) {
+		objs->nents = i;
+		objs->objs[i] = drm_gem_object_lookup(drm_file, handles[i]);
+		if (!objs->objs[i]) {
+			virtio_gpu_array_put_free(objs);
+			return NULL;
+		}
+	}
+	objs->nents = i;
+	return objs;
+}
+
+void virtio_gpu_array_put_free(struct virtio_gpu_object_array *objs)
+{
+	u32 i;
+
+	for (i = 0; i < objs->nents; i++)
+		drm_gem_object_put_unlocked(objs->objs[i]);
+	virtio_gpu_array_free(objs);
+}
-- 
2.18.1