drm/vmwgfx: add proper framebuffer refcounting
Afact vmwgfx already has all the right refcounting implemented on the
backing storage, and we only need to ensure that the drm fb doesn't
disappear untimely. So holding onto the fb reference from _lookup
until vmw_kms_present has completed should be enough.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
index 1b8f428..c509d40 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
@@ -171,8 +171,6 @@
ret = -EINVAL;
goto out_no_fb;
}
- /* fb is protect by the mode_config lock, so drop the ref immediately */
- drm_framebuffer_unreference(fb);
vfb = vmw_framebuffer_to_vfb(fb);
ret = ttm_read_lock(&vmaster->lock, true);
@@ -197,6 +195,7 @@
out_no_surface:
ttm_read_unlock(&vmaster->lock);
out_no_ttm_lock:
+ drm_framebuffer_unreference(fb);
out_no_fb:
drm_modeset_unlock_all(dev);
out_no_copy:
@@ -256,14 +255,12 @@
ret = -EINVAL;
goto out_no_fb;
}
- /* fb is protect by the mode_config lock, so drop the ref immediately */
- drm_framebuffer_unreference(fb);
vfb = vmw_framebuffer_to_vfb(fb);
if (!vfb->dmabuf) {
DRM_ERROR("Framebuffer not dmabuf backed.\n");
ret = -EINVAL;
- goto out_no_fb;
+ goto out_no_ttm_lock;
}
ret = ttm_read_lock(&vmaster->lock, true);
@@ -276,6 +273,7 @@
ttm_read_unlock(&vmaster->lock);
out_no_ttm_lock:
+ drm_framebuffer_unreference(fb);
out_no_fb:
drm_modeset_unlock_all(dev);
out_no_copy: