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Re: prop_*_internalize and copyin/out for syscall ?

On Jan,Monday 17 2011, at 6:00 PM, Manuel Bouyer wrote:

> On Mon, Jan 17, 2011 at 04:33:25PM +0100, Manuel Bouyer wrote:
>> [sorry for the cross-post, but I can't decide which list is more appropriate
>> than the other :) ]
>> Hello,
>> so I'm evaluating how to use proplib for the new quotactl(2) I'm working on.
>> I see there is already provision of function to pass property list between
>> kernel and userland using ioctl, but there is no equivalent for syscalls.
>> Should there be ?
>> For kernel land, prop_{array,dictionary}_copy{in,out} would do it
>> (prop_{array,dictionary}_copyout is documented but not implemented,
>> this is easy).
>> For userland, we probably need a prop_{array,dictionary}_recv_syscall(),
>> wich takes as parameter the pref we got from kernel, and internalize it.
>> Parameters would be the pref, and a pointer to the prop_array_t or
>> prop_dictionary_t that will get the result. What this would do in
>> addition to call prop_{array,dictionary}_internalize_from_pref() is
>> to unmap the buffer the kernel mmaped for us. I don't think this details of 
>> the
>> kernel/userland communication should be exposed outside of the
>> proplib code.
>> For symetry, we probably want a prop_{array,dictionary}_send_syscall()
>> which is just an alias to prop_{array,dictionary}_externalize_to_pref()
>> Comments ?
> here is a diff implementing the above
> -- 
> Manuel Bouyer <>
>     NetBSD: 26 ans d'experience feront toujours la difference
> --
> <proplib.diff>

I think this patch looks fine. You should commit it.



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