Re: copy_to/from_use query?

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copy_to_user/copy_from_user takes care of address not in memory (page
fault), For x86 atleast u can do blind memcpy ( it not
recommended/portable though ).
Pl. correct me if i am wrong.

On Mon, 11 Oct 2004 09:41:30 +0200, Jan Hudec <bulb@xxxxxx> wrote:
> On Mon, Oct 11, 2004 at 09:55:37 +0530, mohanlal jangir wrote:
> > I have a character device and some of its functions are being called by
> > ioctl. In a function, I do copy_to_user and copy_from_user to get the user
> > space data in kernel memory. My question is, if this function doesn't sleep,
> > can I avoid calls to copy_to_user and copy_from_user?
> 
> No, you can't. The user-space memory is not directly addressable from
> kernel.
> 
> -------------------------------------------------------------------------------
>                                                  Jan 'Bulb' Hudec <bulb@xxxxxx>
> 
> 
>

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