The GEM mmap code relies on the GEM object's mmap callback to set the
VMA's vm_ops field. This is easily forgotten and already led to a memory
leak in the CMA helpers. Instead set the vm_ops field in the DRM core
code to the GEM object's value. Drivers with different needs can override
this in their mmap callback.
v2:
* support (vm_ops == NULL) if mmap is given; required by VRAM
helpers
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes:
f5ca8eb6f9bd ("drm/cma-helper: Implement mmap as GEM CMA object functions")
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reported-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Tested-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eric Anholt <eric@anholt.net>
Cc: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210115093038.10345-1-tzimmermann@suse.de
drm_gem_object_get(obj);
vma->vm_private_data = obj;
+ vma->vm_ops = obj->funcs->vm_ops;
if (obj->funcs->mmap) {
ret = obj->funcs->mmap(obj, vma);
- if (ret) {
- drm_gem_object_put(obj);
- return ret;
- }
+ if (ret)
+ goto err_drm_gem_object_put;
WARN_ON(!(vma->vm_flags & VM_DONTEXPAND));
} else {
- if (obj->funcs->vm_ops)
- vma->vm_ops = obj->funcs->vm_ops;
- else {
- drm_gem_object_put(obj);
- return -EINVAL;
+ if (!vma->vm_ops) {
+ ret = -EINVAL;
+ goto err_drm_gem_object_put;
}
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
}
return 0;
+
+err_drm_gem_object_put:
+ drm_gem_object_put(obj);
+ return ret;
}
EXPORT_SYMBOL(drm_gem_mmap_obj);
vma->vm_pgoff += drm_vma_node_start(&obj->vma_node);
if (obj->funcs && obj->funcs->mmap) {
+ vma->vm_ops = obj->funcs->vm_ops;
+
ret = obj->funcs->mmap(obj, vma);
if (ret)
return ret;