Re: File copy system call proposal

[H. Peter Anvin]

Followup to:  <[e-mail]>
By author:    Quinn Harris <[e-mail]>
In newsgroup: linux.dev.kernel
> 
> All kernel copy:
> Commands like cp and install open the source and destination file using
> the open sys call.  The data from the source is copied to the
> destination by repeatedly calling the read then write sys calls.  This
> process involves copying the data in the file from kernel memory space
> to the user memory space and back again.  Note that all this copying is
> done by the kernel upon calling read or write.  I would expect if this
> can be moved completely into the kernel no memory copy operations would
> be performed by the processor by using hardware DMA.
> 

mmap(source file);
write(target file, mmap region);

	-hpa
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