There are some concerns with this, as the DRM will be setting the nonsecure
flag on the batchbuffer, and the server may be submitting some secure-only
commands. It appears to work on the 915GM test system currently.
The EmitFlush in i830_dri.c was added as a pageflipping workaround, and was
noted to not even be sufficient then. There's no reason for it to be there,
so it's removed. After that, we just have to not emit an MI_FLUSH if we
already had, and cursor movement no longer bashes memory manager.
Eric Anholt