drm/gem-shmem: Set vm_ops in static initializer

Initialize default vm_ops in static initialization of the GEM SHMEM funcs,
instead of the mmap code. It's simply better style. GEM helpers will later
set a VMA's vm_ops from the default automatically.

v2:
	* also update the drivers that build upon GEM SHMEM
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209155634.3994-2-tzimmermann@suse.de

drivers/gpu/drm/drm_gem_shmem_helper.c

@@ -46,6 +46,7 @@ static const struct drm_gem_object_funcs drm_gem_shmem_funcs = {
 	.vmap = drm_gem_shmem_object_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = drm_gem_shmem_object_mmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
 };
 
 static struct drm_gem_shmem_object *
@@ -585,11 +586,12 @@ static void drm_gem_shmem_vm_close(struct vm_area_struct *vma)
 	drm_gem_vm_close(vma);
 }
 
-static const struct vm_operations_struct drm_gem_shmem_vm_ops = {
+const struct vm_operations_struct drm_gem_shmem_vm_ops = {
 	.fault = drm_gem_shmem_fault,
 	.open = drm_gem_shmem_vm_open,
 	.close = drm_gem_shmem_vm_close,
 };
+EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_ops);
 
 /**
  * drm_gem_shmem_mmap - Memory-map a shmem GEM object
@@ -625,7 +627,6 @@ int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct
 	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 	if (shmem->map_wc)
 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
-	vma->vm_ops = &drm_gem_shmem_vm_ops;
 
 	return 0;
 }

drivers/gpu/drm/lima/lima_gem.c

@@ -213,6 +213,7 @@ static const struct drm_gem_object_funcs lima_gem_funcs = {
 	.vmap = lima_gem_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = lima_gem_mmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
 };
 
 struct drm_gem_object *lima_gem_create_object(struct drm_device *dev, size_t size)

drivers/gpu/drm/panfrost/panfrost_gem.c

@@ -206,6 +206,7 @@ static const struct drm_gem_object_funcs panfrost_gem_funcs = {
 	.vmap = drm_gem_shmem_object_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = drm_gem_shmem_object_mmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
 };
 
 /**

drivers/gpu/drm/v3d/v3d_bo.c

@@ -59,6 +59,7 @@ static const struct drm_gem_object_funcs v3d_gem_funcs = {
 	.vmap = drm_gem_shmem_object_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = drm_gem_shmem_object_mmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
 };
 
 /* gem_create_object function for allocating a BO struct and doing

drivers/gpu/drm/virtio/virtgpu_object.c

@@ -124,6 +124,7 @@ static const struct drm_gem_object_funcs virtio_gpu_shmem_funcs = {
 	.vmap = drm_gem_shmem_object_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = drm_gem_shmem_object_mmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
 };
 
 bool virtio_gpu_is_shmem(struct virtio_gpu_object *bo)

include/drm/drm_gem_shmem_helper.h

@@ -135,6 +135,8 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem)
 void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
 			      struct drm_printer *p, unsigned int indent);
 
+extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
+
 /*
  * GEM object functions
  */