Using ion memory for direct-io
From: Zengtao (B)
Date: Fri Apr 14 2017 - 05:19:48 EST
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