[PATCH v2 2/2] drm: share address space for dma bufs

[Gerd Hoffmann]

Use the shared address space of the drm device (see drm_open() in
drm_file.c) for dma-bufs too.  That removes a difference betweem drm
device mmap vmas and dma-buf mmap vmas and fixes corner cases like
dropping ptes (using madvise(DONTNEED) for example) not working
properly.

Also remove amdgpu driver's private dmabuf update.  It is not needed
any more now that we are doing this for everybody.

Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 4 +---
 drivers/gpu/drm/drm_prime.c                 | 4 +++-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index d5bcdfefbad6..586db4fb46bd 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -361,10 +361,8 @@ struct dma_buf *amdgpu_gem_prime_export(struct drm_gem_object *gobj,
 		return ERR_PTR(-EPERM);
 
 	buf = drm_gem_prime_export(gobj, flags);
-	if (!IS_ERR(buf)) {
-		buf->file->f_mapping = gobj->dev->anon_inode->i_mapping;
+	if (!IS_ERR(buf))
 		buf->ops = &amdgpu_dmabuf_ops;
-	}
 
 	return buf;
 }
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index a9633bd241bb..c3fc341453c0 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -240,6 +240,7 @@ void drm_prime_destroy_file_private(struct drm_prime_file_private *prime_fpriv)
 struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
 				      struct dma_buf_export_info *exp_info)
 {
+	struct drm_gem_object *obj = exp_info->priv;
 	struct dma_buf *dma_buf;
 
 	dma_buf = dma_buf_export(exp_info);
@@ -247,7 +248,8 @@ struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
 		return dma_buf;
 
 	drm_dev_get(dev);
-	drm_gem_object_get(exp_info->priv);
+	drm_gem_object_get(obj);
+	dma_buf->file->f_mapping = obj->dev->anon_inode->i_mapping;
 
 	return dma_buf;
 }
-- 
2.18.1