1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/gpu/drm/virtio/virtgpu_prime.c b/drivers/gpu/drm/virtio/virtgpu_prime.c
new file mode 100644
index 000000000000..ce49282198cb
--- /dev/null
+++ b/drivers/gpu/drm/virtio/virtgpu_prime.c
@@ -0,0 +1,349 @@
+/*
+ * Copyright 2014 Canonical
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Andreas Pokorny
+ */
+
+#include <drm/drm_prime.h>
+#include <linux/virtio_dma_buf.h>
+
+#include "virtgpu_drv.h"
+
+MODULE_IMPORT_NS("DMA_BUF");
+
+static int virtgpu_virtio_get_uuid(struct dma_buf *buf,
+				   uuid_t *uuid)
+{
+	struct drm_gem_object *obj = buf->priv;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+	struct virtio_gpu_device *vgdev = obj->dev->dev_private;
+
+	wait_event(vgdev->resp_wq, bo->uuid_state != STATE_INITIALIZING);
+	if (bo->uuid_state != STATE_OK)
+		return -ENODEV;
+
+	uuid_copy(uuid, &bo->uuid);
+
+	return 0;
+}
+
+static struct sg_table *
+virtgpu_gem_map_dma_buf(struct dma_buf_attachment *attach,
+			enum dma_data_direction dir)
+{
+	struct drm_gem_object *obj = attach->dmabuf->priv;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+
+	if (virtio_gpu_is_vram(bo))
+		return virtio_gpu_vram_map_dma_buf(bo, attach->dev, dir);
+
+	return drm_gem_map_dma_buf(attach, dir);
+}
+
+static void virtgpu_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
+				      struct sg_table *sgt,
+				      enum dma_data_direction dir)
+{
+	struct drm_gem_object *obj = attach->dmabuf->priv;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+
+	if (virtio_gpu_is_vram(bo)) {
+		virtio_gpu_vram_unmap_dma_buf(attach->dev, sgt, dir);
+		return;
+	}
+
+	drm_gem_unmap_dma_buf(attach, sgt, dir);
+}
+
+static const struct virtio_dma_buf_ops virtgpu_dmabuf_ops =  {
+	.ops = {
+		.attach = virtio_dma_buf_attach,
+		.detach = drm_gem_map_detach,
+		.map_dma_buf = virtgpu_gem_map_dma_buf,
+		.unmap_dma_buf = virtgpu_gem_unmap_dma_buf,
+		.release = drm_gem_dmabuf_release,
+		.mmap = drm_gem_dmabuf_mmap,
+		.vmap = drm_gem_dmabuf_vmap,
+		.vunmap = drm_gem_dmabuf_vunmap,
+	},
+	.device_attach = drm_gem_map_attach,
+	.get_uuid = virtgpu_virtio_get_uuid,
+};
+
+int virtio_gpu_resource_assign_uuid(struct virtio_gpu_device *vgdev,
+				    struct virtio_gpu_object *bo)
+{
+	struct virtio_gpu_object_array *objs;
+
+	objs = virtio_gpu_array_alloc(1);
+	if (!objs)
+		return -ENOMEM;
+
+	virtio_gpu_array_add_obj(objs, &bo->base.base);
+
+	return virtio_gpu_cmd_resource_assign_uuid(vgdev, objs);
+}
+
+struct dma_buf *virtgpu_gem_prime_export(struct drm_gem_object *obj,
+					 int flags)
+{
+	struct dma_buf *buf;
+	struct drm_device *dev = obj->dev;
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+	int ret = 0;
+	bool blob = bo->host3d_blob || bo->guest_blob;
+	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+	if (!blob) {
+		if (vgdev->has_resource_assign_uuid) {
+			ret = virtio_gpu_resource_assign_uuid(vgdev, bo);
+			if (ret)
+				return ERR_PTR(ret);
+
+			virtio_gpu_notify(vgdev);
+		} else {
+			bo->uuid_state = STATE_ERR;
+		}
+	} else if (!(bo->blob_flags & VIRTGPU_BLOB_FLAG_USE_CROSS_DEVICE)) {
+		bo->uuid_state = STATE_ERR;
+	}
+
+	exp_info.ops = &virtgpu_dmabuf_ops.ops;
+	exp_info.size = obj->size;
+	exp_info.flags = flags;
+	exp_info.priv = obj;
+	exp_info.resv = obj->resv;
+
+	buf = virtio_dma_buf_export(&exp_info);
+	if (IS_ERR(buf))
+		return buf;
+
+	drm_dev_get(dev);
+	drm_gem_object_get(obj);
+
+	return buf;
+}
+
+int virtgpu_dma_buf_import_sgt(struct virtio_gpu_mem_entry **ents,
+			       unsigned int *nents,
+			       struct virtio_gpu_object *bo,
+			       struct dma_buf_attachment *attach)
+{
+	struct scatterlist *sl;
+	struct sg_table *sgt;
+	long i, ret;
+
+	dma_resv_assert_held(attach->dmabuf->resv);
+
+	ret = dma_resv_wait_timeout(attach->dmabuf->resv,
+				    DMA_RESV_USAGE_KERNEL,
+				    false, MAX_SCHEDULE_TIMEOUT);
+	if (ret <= 0)
+		return ret < 0 ? ret : -ETIMEDOUT;
+
+	sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
+	if (IS_ERR(sgt))
+		return PTR_ERR(sgt);
+
+	*ents = kvmalloc_array(sgt->nents,
+			       sizeof(struct virtio_gpu_mem_entry),
+			       GFP_KERNEL);
+	if (!(*ents)) {
+		dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
+		return -ENOMEM;
+	}
+
+	*nents = sgt->nents;
+	for_each_sgtable_dma_sg(sgt, sl, i) {
+		(*ents)[i].addr = cpu_to_le64(sg_dma_address(sl));
+		(*ents)[i].length = cpu_to_le32(sg_dma_len(sl));
+		(*ents)[i].padding = 0;
+	}
+
+	bo->sgt = sgt;
+	return 0;
+}
+
+static void virtgpu_dma_buf_unmap(struct virtio_gpu_object *bo)
+{
+	struct dma_buf_attachment *attach = bo->base.base.import_attach;
+
+	dma_resv_assert_held(attach->dmabuf->resv);
+
+	if (bo->created) {
+		virtio_gpu_detach_object_fenced(bo);
+
+		if (bo->sgt)
+			dma_buf_unmap_attachment(attach, bo->sgt,
+						 DMA_BIDIRECTIONAL);
+
+		bo->sgt = NULL;
+	}
+}
+
+static void virtgpu_dma_buf_free_obj(struct drm_gem_object *obj)
+{
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+	struct virtio_gpu_device *vgdev = obj->dev->dev_private;
+	struct dma_buf_attachment *attach = obj->import_attach;
+
+	if (drm_gem_is_imported(obj)) {
+		struct dma_buf *dmabuf = attach->dmabuf;
+
+		dma_resv_lock(dmabuf->resv, NULL);
+		virtgpu_dma_buf_unmap(bo);
+		dma_resv_unlock(dmabuf->resv);
+
+		dma_buf_detach(dmabuf, attach);
+		dma_buf_put(dmabuf);
+	}
+
+	if (bo->created) {
+		virtio_gpu_cmd_unref_resource(vgdev, bo);
+		virtio_gpu_notify(vgdev);
+		return;
+	}
+	virtio_gpu_cleanup_object(bo);
+}
+
+static int virtgpu_dma_buf_init_obj(struct drm_device *dev,
+				    struct virtio_gpu_object *bo,
+				    struct dma_buf_attachment *attach)
+{
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct virtio_gpu_object_params params = { 0 };
+	struct dma_resv *resv = attach->dmabuf->resv;
+	struct virtio_gpu_mem_entry *ents = NULL;
+	unsigned int nents;
+	int ret;
+
+	ret = virtio_gpu_resource_id_get(vgdev, &bo->hw_res_handle);
+	if (ret) {
+		virtgpu_dma_buf_free_obj(&bo->base.base);
+		return ret;
+	}
+
+	dma_resv_lock(resv, NULL);
+
+	ret = dma_buf_pin(attach);
+	if (ret)
+		goto err_pin;
+
+	ret = virtgpu_dma_buf_import_sgt(&ents, &nents, bo, attach);
+	if (ret)
+		goto err_import;
+
+	params.blob = true;
+	params.blob_mem = VIRTGPU_BLOB_MEM_GUEST;
+	params.blob_flags = VIRTGPU_BLOB_FLAG_USE_SHAREABLE;
+	params.size = attach->dmabuf->size;
+
+	virtio_gpu_cmd_resource_create_blob(vgdev, bo, &params,
+					    ents, nents);
+	bo->guest_blob = true;
+
+	dma_buf_unpin(attach);
+	dma_resv_unlock(resv);
+
+	return 0;
+
+err_import:
+	dma_buf_unpin(attach);
+err_pin:
+	dma_resv_unlock(resv);
+	virtgpu_dma_buf_free_obj(&bo->base.base);
+	return ret;
+}
+
+static const struct drm_gem_object_funcs virtgpu_gem_dma_buf_funcs = {
+	.free = virtgpu_dma_buf_free_obj,
+};
+
+static void virtgpu_dma_buf_move_notify(struct dma_buf_attachment *attach)
+{
+	struct drm_gem_object *obj = attach->importer_priv;
+	struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+
+	virtgpu_dma_buf_unmap(bo);
+}
+
+static const struct dma_buf_attach_ops virtgpu_dma_buf_attach_ops = {
+	.allow_peer2peer = true,
+	.move_notify = virtgpu_dma_buf_move_notify
+};
+
+struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev,
+						struct dma_buf *buf)
+{
+	struct virtio_gpu_device *vgdev = dev->dev_private;
+	struct dma_buf_attachment *attach;
+	struct virtio_gpu_object *bo;
+	struct drm_gem_object *obj;
+	int ret;
+
+	if (buf->ops == &virtgpu_dmabuf_ops.ops) {
+		obj = buf->priv;
+		if (obj->dev == dev) {
+			/*
+			 * Importing dmabuf exported from our own gem increases
+			 * refcount on gem itself instead of f_count of dmabuf.
+			 */
+			drm_gem_object_get(obj);
+			return obj;
+		}
+	}
+
+	if (!vgdev->has_resource_blob || vgdev->has_virgl_3d)
+		return drm_gem_prime_import(dev, buf);
+
+	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
+	if (!bo)
+		return ERR_PTR(-ENOMEM);
+
+	obj = &bo->base.base;
+	obj->resv = buf->resv;
+	obj->funcs = &virtgpu_gem_dma_buf_funcs;
+	drm_gem_private_object_init(dev, obj, buf->size);
+
+	attach = dma_buf_dynamic_attach(buf, dev->dev,
+					&virtgpu_dma_buf_attach_ops, obj);
+	if (IS_ERR(attach)) {
+		kfree(bo);
+		return ERR_CAST(attach);
+	}
+
+	obj->import_attach = attach;
+	get_dma_buf(buf);
+
+	ret = virtgpu_dma_buf_init_obj(dev, bo, attach);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	return obj;
+}
+
+struct drm_gem_object *virtgpu_gem_prime_import_sg_table(
+	struct drm_device *dev, struct dma_buf_attachment *attach,
+	struct sg_table *table)
+{
+	return ERR_PTR(-ENODEV);
+}