drm/radeon: use prime helpers

Simplify the Radeon prime implementation by using the default behavior provided
by drm_gem_prime_import and drm_gem_prime_export.

v2:
- Rename functions to radeon_gem_prime_get_sg_table and
  radeon_gem_prime_import_sg_table.
- Delete the now-unused vmapping_count variable.

Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon.h

@@ -350,7 +350,6 @@ struct radeon_bo {
 	struct drm_gem_object		gem_base;
 
 	struct ttm_bo_kmap_obj dma_buf_vmap;
-	int vmapping_count;
 };
 #define gem_to_radeon_bo(gobj) container_of((gobj), struct radeon_bo, gem_base)
 

drivers/gpu/drm/radeon/radeon_drv.c

@@ -118,11 +118,13 @@ int radeon_mode_dumb_create(struct drm_file *file_priv,
 int radeon_mode_dumb_destroy(struct drm_file *file_priv,
 			     struct drm_device *dev,
 			     uint32_t handle);
-struct dma_buf *radeon_gem_prime_export(struct drm_device *dev,
-					struct drm_gem_object *obj,
-					int flags);
-struct drm_gem_object *radeon_gem_prime_import(struct drm_device *dev,
-					       struct dma_buf *dma_buf);
+struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj);
+struct drm_gem_object *radeon_gem_prime_import_sg_table(struct drm_device *dev,
+							size_t size,
+							struct sg_table *sg);
+int radeon_gem_prime_pin(struct drm_gem_object *obj);
+void *radeon_gem_prime_vmap(struct drm_gem_object *obj);
+void radeon_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
 extern long radeon_kms_compat_ioctl(struct file *filp, unsigned int cmd,
 				    unsigned long arg);
 
@@ -409,8 +411,13 @@ static struct drm_driver kms_driver = {
 
 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
-	.gem_prime_export = radeon_gem_prime_export,
-	.gem_prime_import = radeon_gem_prime_import,
+	.gem_prime_export = drm_gem_prime_export,
+	.gem_prime_import = drm_gem_prime_import,
+	.gem_prime_pin = radeon_gem_prime_pin,
+	.gem_prime_get_sg_table = radeon_gem_prime_get_sg_table,
+	.gem_prime_import_sg_table = radeon_gem_prime_import_sg_table,
+	.gem_prime_vmap = radeon_gem_prime_vmap,
+	.gem_prime_vunmap = radeon_gem_prime_vunmap,
 
 	.name = DRIVER_NAME,
 	.desc = DRIVER_DESC,

drivers/gpu/drm/radeon/radeon_prime.c

@@ -28,199 +28,71 @@
 #include "radeon.h"
 #include <drm/radeon_drm.h>
 
-#include <linux/dma-buf.h>
-
-static struct sg_table *radeon_gem_map_dma_buf(struct dma_buf_attachment *attachment,
-					       enum dma_data_direction dir)
+struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj)
 {
-	struct radeon_bo *bo = attachment->dmabuf->priv;
-	struct drm_device *dev = bo->rdev->ddev;
+	struct radeon_bo *bo = gem_to_radeon_bo(obj);
 	int npages = bo->tbo.num_pages;
-	struct sg_table *sg;
-	int nents;
-
-	mutex_lock(&dev->struct_mutex);
-	sg = drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages);
-	nents = dma_map_sg(attachment->dev, sg->sgl, sg->nents, dir);
-	mutex_unlock(&dev->struct_mutex);
-	return sg;
-}
-
-static void radeon_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
-				     struct sg_table *sg, enum dma_data_direction dir)
-{
-	dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
-	sg_free_table(sg);
-	kfree(sg);
-}
-
-static void radeon_gem_dmabuf_release(struct dma_buf *dma_buf)
-{
-	struct radeon_bo *bo = dma_buf->priv;
-
-	if (bo->gem_base.export_dma_buf == dma_buf) {
-		DRM_ERROR("unreference dmabuf %p\n", &bo->gem_base);
-		bo->gem_base.export_dma_buf = NULL;
-		drm_gem_object_unreference_unlocked(&bo->gem_base);
-	}
-}
-
-static void *radeon_gem_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
-{
-	return NULL;
-}
-
-static void radeon_gem_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
-{
-
-}
-static void *radeon_gem_kmap(struct dma_buf *dma_buf, unsigned long page_num)
-{
-	return NULL;
-}
-
-static void radeon_gem_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
-{
 
+	return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages);
 }
 
-static int radeon_gem_prime_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
+void *radeon_gem_prime_vmap(struct drm_gem_object *obj)
 {
-	return -EINVAL;
-}
-
-static void *radeon_gem_prime_vmap(struct dma_buf *dma_buf)
-{
-	struct radeon_bo *bo = dma_buf->priv;
-	struct drm_device *dev = bo->rdev->ddev;
+	struct radeon_bo *bo = gem_to_radeon_bo(obj);
 	int ret;
 
-	mutex_lock(&dev->struct_mutex);
-	if (bo->vmapping_count) {
-		bo->vmapping_count++;
-		goto out_unlock;
-	}
-
 	ret = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages,
 			  &bo->dma_buf_vmap);
-	if (ret) {
-		mutex_unlock(&dev->struct_mutex);
+	if (ret)
 		return ERR_PTR(ret);
-	}
-	bo->vmapping_count = 1;
-out_unlock:
-	mutex_unlock(&dev->struct_mutex);
+
 	return bo->dma_buf_vmap.virtual;
 }
 
-static void radeon_gem_prime_vunmap(struct dma_buf *dma_buf, void *vaddr)
+void radeon_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
 {
-	struct radeon_bo *bo = dma_buf->priv;
-	struct drm_device *dev = bo->rdev->ddev;
+	struct radeon_bo *bo = gem_to_radeon_bo(obj);
 
-	mutex_lock(&dev->struct_mutex);
-	bo->vmapping_count--;
-	if (bo->vmapping_count == 0) {
-		ttm_bo_kunmap(&bo->dma_buf_vmap);
-	}
-	mutex_unlock(&dev->struct_mutex);
+	ttm_bo_kunmap(&bo->dma_buf_vmap);
 }
-const static struct dma_buf_ops radeon_dmabuf_ops =  {
-	.map_dma_buf = radeon_gem_map_dma_buf,
-	.unmap_dma_buf = radeon_gem_unmap_dma_buf,
-	.release = radeon_gem_dmabuf_release,
-	.kmap = radeon_gem_kmap,
-	.kmap_atomic = radeon_gem_kmap_atomic,
-	.kunmap = radeon_gem_kunmap,
-	.kunmap_atomic = radeon_gem_kunmap_atomic,
-	.mmap = radeon_gem_prime_mmap,
-	.vmap = radeon_gem_prime_vmap,
-	.vunmap = radeon_gem_prime_vunmap,
-};
-
-static int radeon_prime_create(struct drm_device *dev,
-			       size_t size,
-			       struct sg_table *sg,
-			       struct radeon_bo **pbo)
+
+struct drm_gem_object *radeon_gem_prime_import_sg_table(struct drm_device *dev,
+							size_t size,
+							struct sg_table *sg)
 {
 	struct radeon_device *rdev = dev->dev_private;
 	struct radeon_bo *bo;
 	int ret;
 
 	ret = radeon_bo_create(rdev, size, PAGE_SIZE, false,
-			       RADEON_GEM_DOMAIN_GTT, sg, pbo);
+			       RADEON_GEM_DOMAIN_GTT, sg, &bo);
 	if (ret)
-		return ret;
-	bo = *pbo;
+		return ERR_PTR(ret);
 	bo->gem_base.driver_private = bo;
 
 	mutex_lock(&rdev->gem.mutex);
 	list_add_tail(&bo->list, &rdev->gem.objects);
 	mutex_unlock(&rdev->gem.mutex);
 
-	return 0;
+	return &bo->gem_base;
 }
 
-struct dma_buf *radeon_gem_prime_export(struct drm_device *dev,
-					struct drm_gem_object *obj,
-					int flags)
+int radeon_gem_prime_pin(struct drm_gem_object *obj)
 {
 	struct radeon_bo *bo = gem_to_radeon_bo(obj);
 	int ret = 0;
 
 	ret = radeon_bo_reserve(bo, false);
 	if (unlikely(ret != 0))
-		return ERR_PTR(ret);
+		return ret;
 
 	/* pin buffer into GTT */
 	ret = radeon_bo_pin(bo, RADEON_GEM_DOMAIN_GTT, NULL);
 	if (ret) {
 		radeon_bo_unreserve(bo);
-		return ERR_PTR(ret);
+		return ret;
 	}
 	radeon_bo_unreserve(bo);
-	return dma_buf_export(bo, &radeon_dmabuf_ops, obj->size, flags);
-}
 
-struct drm_gem_object *radeon_gem_prime_import(struct drm_device *dev,
-					       struct dma_buf *dma_buf)
-{
-	struct dma_buf_attachment *attach;
-	struct sg_table *sg;
-	struct radeon_bo *bo;
-	int ret;
-
-	if (dma_buf->ops == &radeon_dmabuf_ops) {
-		bo = dma_buf->priv;
-		if (bo->gem_base.dev == dev) {
-			drm_gem_object_reference(&bo->gem_base);
-			dma_buf_put(dma_buf);
-			return &bo->gem_base;
-		}
-	}
-
-	/* need to attach */
-	attach = dma_buf_attach(dma_buf, dev->dev);
-	if (IS_ERR(attach))
-		return ERR_CAST(attach);
-
-	sg = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
-	if (IS_ERR(sg)) {
-		ret = PTR_ERR(sg);
-		goto fail_detach;
-	}
-
-	ret = radeon_prime_create(dev, dma_buf->size, sg, &bo);
-	if (ret)
-		goto fail_unmap;
-
-	bo->gem_base.import_attach = attach;
-
-	return &bo->gem_base;
-
-fail_unmap:
-	dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
-fail_detach:
-	dma_buf_detach(dma_buf, attach);
-	return ERR_PTR(ret);
+	return 0;
 }