drm/tegra: gem: Make __tegra_gem_mmap() available more widely

This function allows mapping a GEM object into a virtual memory address
space, which makes it useful outside of the GEM code.

While at it, rename the function so it doesn't clash with the function
that implements the DRM_TEGRA_GEM_MMAP IOCTL.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/gem.c

@@ -459,8 +459,7 @@ const struct vm_operations_struct tegra_bo_vm_ops = {
 	.close = drm_gem_vm_close,
 };
 
-static int tegra_gem_mmap(struct drm_gem_object *gem,
-			  struct vm_area_struct *vma)
+int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
 {
 	struct tegra_bo *bo = to_tegra_bo(gem);
 
@@ -507,7 +506,7 @@ int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
 
 	gem = vma->vm_private_data;
 
-	return tegra_gem_mmap(gem, vma);
+	return __tegra_gem_mmap(gem, vma);
 }
 
 static struct sg_table *
@@ -600,7 +599,7 @@ static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
 	if (err < 0)
 		return err;
 
-	return tegra_gem_mmap(gem, vma);
+	return __tegra_gem_mmap(gem, vma);
 }
 
 static void *tegra_gem_prime_vmap(struct dma_buf *buf)

drivers/gpu/drm/tegra/gem.h

@@ -70,6 +70,7 @@ int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
 
 extern const struct vm_operations_struct tegra_bo_vm_ops;
 
+int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma);
 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma);
 
 struct dma_buf *tegra_gem_prime_export(struct drm_device *drm,