> hi,
> 
> 1. the recent filehandle changes reduced opaqueness of filehandles.
>   ie. syscalls now determine the size of handles from fid_len.
>   how about adding an explicit size argument to fhopen and friends instead,
>   so that we can keep filehandles opaque and we don't need to have
>   an ugly copyin-twice hack in kernel?
> 
> 2. how about unexporting fhandle_t from userland completely?
>   ie. make them void *.  as filehandle is now variable sized,
>   there isn't much point to represent it as a C structure.
>   (this can be done without abi change.)
> 
> int getfh(const char *path, void *fhp, size_t *size);
> int fhopen(const void *fhp, size_t size, int flags);

as i'm not sure i can do it in timely manner,
i'd like to backout VFS_MAXFIDSIZ removal and system call part of
your changes for now.

any objection?

YAMAMOTO Takashi