RE: mapping memory from one process to another

["Rob Fuller" <rfuller@NSISW.COM>]

I oversimplified the problem.  Suppose I want to write a file system
that shares the buffers passed into read/write system calls with a
different user-mode process.  To achieve this efficiently (i.e.  without
copying the buffers,) I need to temporarily map the buffers that are
passed into my file system into my user-mode process.  Because any
process may be using my file system, the buffer will not originate in my
driver.

> -----Original Message-----
> From: Rik van Riel [mailto:riel@conectiva.com.br]
> Sent: Wednesday, August 01, 2001 4:54 PM
> To: Rob Fuller
> Cc: kernelnewbies@nl.linux.org
> Subject: Re: mapping memory from one process to another
> 
> 
> On Wed, 1 Aug 2001, Rob Fuller wrote:
> 
> > I want to temporarily map a buffer that is passed to my driver
> > through an ioctl into another process's address space.  I do not
> > want to copy the data.  Any ideas?
> 
> Let the buffer originate in the driver in the
> first place.
> 
> Ie. let the first program (the one which does
> ioctl now) mmap() some control buffer of the
> driver.
> 
> Now the memory is inside the driver and thus
> very easy to pass on to the second program.
> 
> regards,
> 
> Rik
> --
> Executive summary of a recent Microsoft press release:
>    "we are concerned about the GNU General Public License (GPL)"
> 
> 
> 		http://www.surriel.com/
> http://www.conectiva.com/	http://distro.conectiva.com/
> 
> 
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