Hi Currently, the ion mapped to userspace will be forced with VM_IO and VM_PFNMAP flags. When I use the ion memory to do the direct-io, it will fail when reaching the get_user_pages, Back to the VM_IO and VM_PFNMAP flag, there two flags are introduced by the remap_pfn_range called by the ion_heap_mmap_user. >From my point of view, all ion memory(cma/vmalloc/system heap) are managed by linux vm, it is not reasonable to have the VM_IO and VM_PFNMAP flag, but I don't any suitable function to replace the remap_pfn_range, any suggestions? Thanks && Regards Zengtao _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel